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INDEX Description Page no : Section 1 Introduction 1.1 Definition 1.2 Types Of Peptic Ulcer 1.3 Prevalence of Peptic Ulcer 1.4 Pathophysiology 1.4.1 Defensive factors 1.4.2 Aggressive factors Section 2 Peptic Ulcer Disease 2.1 Signs and symptoms 2.2 Causes 2.3 Risk increases with: both in DU and GU 2.4 Appropriate Health care 2.5 Possible major complications 2.6 Diet 2.7 General measures 2.8 Surgery 2.9 Inestigations A) Fibreoptic endoscopy B) Barium contrast Radiography C) Secretary tests and Serum Gastrin Levels Section 3 Aim of Treatment 3.1 Gastric Oulet Obstruction 3.2 Penetration 3.3 Perforation Section 4 Drugs used in management of Ulcers 4.1 neutralizing agent 4.1.1 antacids A) Mechanism of action B) Clinical uses C) Dosage D) Pharmacokinetics E) Adverse reaction and precaution F) Drug interaction G) Patient instruction H) Trade name 4.2 Antisecratory agent 4.2.1 Histamine H2 receptor blockers A) Regulation of Acid Secretion B) Mechanism of action C) Clinical uses D) Dosage E) Patient instruction F) clinical uses G) Pharmacokinetics H) Adverse reaction and precaution I) Drug interaction J) Trade name. 4.2.2 Gastric acid proton pump inhibitors A) mechanism of HCL transport B) mechanism of action of PPIs C) Dosage D) Clinical uses E) patient instruction F) Pharmacokinetics G) adverse reaction and precaution H) drug interaction I) Trade name 4.2.3 Selective antimuscarinic agent 4.3 Mucosal protective agents 4.2.4 chelates and complexes 4.2.4.1 sucralfate A) mechanism of action B) dosage C) patient instruction D) pharmacokinetics E) adverse reaction and precaution F) Drug interactions G) Trade name 4.2.4.2 colloidal Bismuth Sulphate A) mechanism of action B) dosage C) pharmacokinetics D) adverse reaction E) uses F) trade names 4.3.2 Carbenoxolone A) mechanism of action B) Dosage C) Adverse reaction and precaution D) Drug interactions E) Parameters to monitor F) Uses G) Trade name 4.2.5 Prostagladin analogue A) mechanism of action B) dosage C) pharmacokinetics D) adverse reaction and precaution E) drug interaction F) patient instructions G) uses H) trade name Section 5 Helicobacter pylori Infection A) Introduction B) what are helicobacter pylori ? C) Prevalence D) Detection of H.P E)Causes F) Eradication therapy G) Dosage I) Patient instruction J) Illnesses caused. Section 6 Future direction Section 7 Conclusion ACKNOWLEDGMENTS Sincere gratitude was extended to project supervisor Dr.Asim Ahmed, for the continuous follow up, constructive criticism, and valuable comments. The author is indebted to Dr. Rafeeq Abu Shaaban from the Pharmaceutics department, to the support, encouragement and fruitful accompaniment, through out the training and presentation of this project. The author wishes to express special gratitude and thanks to those contributing in this revolutionary, distinctive and advanced Hospital pharmacy training 1: namely Dr. Dana Sallam and the staff of New Medical Center Hospital. Finally the Author wishes to express the heartfelt thanks to Dr Abdul Mola in charge of the central training committee for furnishing the entire clinical pharmacy services as far as this term is concerned. ______________________________________Section 1 Introduction General Introduction: 1.1 Definition: Peptic ulcer disease (PUD) is a chronic inflammatory condition of a heterogeneous group of ulcerative disorders in the upper gastrointestinal tract (G.I) that require acid and pepsin for their formation. Ulcers differ from superficial mucosal erosions in that they extend deeper into the muscularis mucosa. 1.2 Types Of Peptic Ulcer: Duodenal Ulcer occurring in the duodenal bulb (first few centimeters of the duodenum) Gastric Ulcer occurring along the lesser curvature of the stomach. Helicobacter pylori (Hp) associated ulcers. (Chronic ulcers) NSAIDs associated ulcers. (Chronic ulcers) Stress ulcers (acute ulcers) Uncommon ulcers are associated with Zollinger-Ellison syndrome, radiation, chemotherapy and vascular insufficiency. 1.3 Prevalence of Peptic Ulcer: DU occurs in both sexes but more predominant in males. Mainly after age of 40. Common in low social economic group 2 % of GU is malignant where as DU are nerve cancerous. GU occurs in both sexes and all ages. Deaths in people over the age of 75 years associates with the widespread use of NSAIDs. Age trends for ulcer occurrence reveal declining rates in younger men, particularly duodenal ulcer, and increasing rates in older women. Most the PU cases can be managed without drugs. 1.4 Pathophysiology: Without protection, the stomachs own hydrochloric acid and pepsin would eat away at the stomach wall. In order to protect itself the stomach tissue employs a number of defense and repair factors and an imbalance between the Gastric mucosal defense and countervailing aggressive force leads to the ulcer formation. 1.4.1 Defensive factors: (stomach self - protection) i. Secretion of mucus by surface epithelial cells (which is the first line of defense). It protects underlying cells and acts as a lubricant layer between the mucosa and its contents .It also forms a mucus layer that impedes hydrogen ion back diffusion (the permeability of hydrogen ions from the stomach lumen into the gastric mucosa). ii. Columnar epithelial cells, which line the stomach and duodenum, secrete a protective layer of mucus that impedes the movement of acid and pepsin from lumen to mucus. These cells also secrete bicarbonate to create a pH gradient from very acidic at the luminal surface of the mucus layer to nearly neutral at the surface of the underlying mucosa. In the duodenum, neutralization of acid is aided by pancreatic and bleary bicarbonate. iii. Rapid gastric epithelial regeneration and when injured , migrating gastric pit cells are immediately available to restore the damaged surface epithelium. iv. The dense network of capillaries underlying the surface epithelium of the stomach and duodenum ensures a high rate of mucosal blood flow that provides the rapid removal of any substances that may have breached the epithelial barrier, as well as supplying oxygen and nutrients. The reactive hyperemia that follows epithelial damage helps protect the mucosa from toxic v. substances and provides additional buffering capacity in the presence of acid back-diffusion. vi. Endogenous PGE2, produced in gastric and duodenal mucosal cells, stimulate mucus and bicarbonate secretion, maintain mucosal blood flow and participate in epithelial restitution and cell growth. NOTE: In the absence of mucous, acid would begin to attack the first layer of stomach tissue. Normally this would not be a problem because the first layer of stomach tissue is constantly being shed. But if the inner lining is destroyed faster then it can be replaced an ulcer may develop. With enough acidity and continued absence of mucous, the ulcer may grow deep enough to reach the underlying blood flow. When that happens, the ulcer is said to have perforated the stomach wall, allowing stomach acid and pepsin can directly act on the tissue underneath. At this point the person with the perforation would be in considerable danger .If the acid reaches an artery, death may occur without prompt medical attention. 1.4.2 Aggressive factors: i. The parietal or oxyntic cells are located in the mucosa of the fundus and body of the stomach. When stimulated, they secrete acid into the gastric lumen through the secretory canaliculi. Three major endogenous substances acetylcholine, histamine, and gastrin, stimulate specific receptors on the parietal cell to secrete acid. The neurocrine pathway delivers acetylcholine released from postganglionic vagal neurons in the stomach. The paracrine pathway delivers histamine released by mucosal mast or (ECL) Enterochromaffin- like cells. The endocrine pathway delivers gastrin from antral and duodenal G cells. ii. Pepsin elaboration; Acid (parietal cell) + Pepsinogen (chief cell) lie in the gland in the stomach lining they convert Pepsinogen (inactive) to Pepsin (active), in presence of acid. iii. Helicobacter pylori infection. iv. Refluxed bile salts. v. Cigarette smoking is clearly associates with a higher incidence of PUD, although the underlying mechanism is uncertain. vi. Alcohol in high concentration is associated with acute gastric mucosal damage and upper GI bleeding, Diet (eating irregularity), NSAIDs Caffeine is a gastric stimulant, which is responsible in increasing gastric acid. vii. Physical and psychological stress, which may predispose selected patients to PUD or alter the degree of pain or disability that results from an ulcer. viii. ix. Gastro esophageal reflux Genetic factors and blood group O. (the gene for blood group O is associated with an increased incidence in DU). x. People who drink their tea and coffee very hot are mostly to develop PUD than those who have their drinks cooler. _____________________________________________Section 2 Peptic Ulcer Disease . An ulcer in the duodenum, which causes symptoms similar to those of stomach ulcer (gastric ulcer). Where as ulcer that develops in the stomach lining is known as gastric ulcer. 2.1 Signs and symptoms: a) Epigastric pain, is the most common symptom of DU and GU with following characteristics: Burning, gnawing feeling that lasts 30 min to 3 hours; the pain is often interpreted as heartburn in (DU), indigestion of hunger. Pain is usually in the upper abdomen, but occasionally below the breastbone. Many patients with DU describe a typical nocturnal pain that awakens them at night. Since 60% of gastric acid is secreted at night. Ulcer related pain in DU often occurs 1-3 hours after meals and is usually relieved by food. In GU, food may precipitate or accentuate ulcer pain (30 min) Pain usually diminishes or disappears during treatment; recurrence of pain after healing usually indicates a recurrent ulcer. b) Loss of appetite usually In GU, less occurs in DU. c) Recurrent vomiting mainly in GU d) Blood in the stool e) Nausea mainly in GU f) Anemia 2.2 Causes: An ulcer is more likely to develop in anxious, tense or worried person. Patients with DU have an elevated mass of Gastric parietal cells and increased acid secretions, irregular living habits, bacterial infection. Also some disease state associated with an increased risk of peptic ulcer disease includes cirrhosis, chronic pulmonary disease, renal failure, and renal transplantation. Additional, but rare, miscellaneous causes include radiation or chemotherapyinduced, vascular insufficiency (crack, cocaine), and duodenal obstruction. 2.3 Risk increases with: both in DU and GU i. Family history of ulcers ii. Stress iii. Improper diet, irregular meal times iv. Smoking v. Excess alcohol and caffeine consumption, which increases acid secretion. vi. Long-term usage of NSAIDs cortisone, which impairs mucosal defense. 2.4 Appropriate Health care: i. Doctors treatment ii. Hospitalization (in complicated states) during the initial treatment. iii. Psychotherapy or counseling (GU). iv. Self care after diagnosis 2.5 Possible major complications: i. Perforation (erosion of the ulcer through the stomach or duodenal wall), pain of perforation is usually sudden and severe with mortality higher for GU than DU. DU may penetrate the pancreas, biliary tract, or liver. ii. Hemorrhage (when the acid or ulcer breaks a blood vessels), anemia iii. Mechanical obstruction is caused by scarring or edema of the duodenal bulb and can lead to delayed gastric emptying. Symptoms usually occur over several months and include nausea, vomiting and weight loss. iv. Extensive peptic ulcer disease, with increased likelihood of stomach cancer. Malignant change of ulcer in GU 2.6 Patient advice : i. Eat small frequent meals for at least 2 weeks ii. Don’t drink alcohol, after recovery; don’t drink more than 1 or 2 alcoholic drinks a day. iii. Avoid caffeine and any hot spicy food that seems to make symptoms worse. iv. Check stool daily for bleeding v. Sharp sudden persistent stomach pain despite treatment. vi. Check for bloody vomit vii. Diarrhea begins which may be caused by antacids viii. You are usually weak pale, due to anemia 2.7 Surgery: i. Here one fifth of the patient require surgery; Mastectomy. Indication for presence of complication and less often-elective operation. (Du) ii. Indicated when risks and discomfort of ulceration are greater than surgery (DU) and (GU) ii. In (GU) one half of the patient’s vagactomy (cutting out of the vagus nerve which is responsible for stimulation of the acid production), required, if the conservative treatment fails. iii. In (GU) indication for elective operation include slowly healing or unhealed ulcer (malignant). 2.8 Investigations: Initial investigations: i. Full blood count ii. Faecal occult bloods Evidence of anemia or GI blood loss will prompt more detailed investigations. A) Fibreoptic endoscopy i. Facilitates early biopsy of potentially malignant gastric ulcers in GU. ii. Allow biopsy for detection of H.pylori. iii. DU could be detected from other acid-peptic diseases. iv. It detects more than 90% of peptic ulcer B) Barium contrast Radiography When do we use it? i. If endoscopies is not available ii. Is the preferred method for patient with advanced ISH or COAD, since the catheter is irritant iii. It detects 30 % of peptic ulcer. C) Secretary tests and Serum Gastrin Levels recommended in patients unresponsive to therapy or for cases which hypersecretory disease are suspected. ___________________________________________________Section 3 3. Aim of the treatment: i. To relive the symptoms e.g. pain, vomiting and improve quality of life. ii. Accelerate healing of the ulcer. iii. Prevent further complications like hemorrhage, Perforation, Penetration. Prevent recurrence by the maintenance treatment, its important that we don’t use iv. proton pump inhibitor, since it causes complete inhibition of acid, (achlohydria) there for this leads to no digestion of food, no absorption and finally leading to weakness and diarrhea. Complication Of PUD: 3.1 Gastric Outlet Obstruction Narrowing of the lumen in the region of a peptic ulcer, the usual cause of gastric outlet obstruction may result from spasm, acute inflammation and edema, muscle hypertrophy, or contraction of scar tissue. 3.1.1 Symptoms: The primary symptom, persistent emesis, is large volume and free of bile, often containing food recognized as having been eaten 12 to 24 hours earlier. Pain, which may be due to vigorous peristalsis as the stomach attempts to overcome the obstruction, tends to be more constant than previous ulcer pain and may be relieved by vomiting. Patients may be dehydrated and anorexic and are usually constipated. Treatment: a) Endoscopic Dilatation: An ulcerated, stenotic pyloric channel is usually less than 5 mm in diameter, compared to the normal 10 to 20 mm. The considerable experience with endoscopic dilatation of esophageal strictures has now been applied to dilatation of the pylorus in combination with medical treatment of the ulcer disease. b) Surgery: Operative intervention should be considered only after appropriate correction of fluid and electrolyte abnormalities and a trial of medical treatment. The most popular operation is vagotomy and a drainage procedure. 3.2 Penetration: It is Defined as erosion of an ulcer through the entire thickness of the stomach or duodenal wall without leakage of digestive contents into the peritoneal cavity, penetration, or confined perforation, occurs through dense, fibrous adhesions into adjacent structures It may involve the pancreas (the most common site for both gastric and duodenal ulcers), gastrohepatic omentum, biliary tract, liver, greater momentum, mesocolon, or colon. Treatment: Penetrating ulcers usually respond to therapy with H2-receptor antagonists or acid pump blockers. 3.3Perforations: A peptic ulcer is said to have perforated when it extends through the muscle wall and serosa of the gastrointestinal tract, establishing communication between the lumen and an adjacent space or structure. If extension through the wall is sealed by surrounding structures before outflow of luminal contents occurs, the ulcer is said to have penetrated. Treatment: Immediate management of a perforated ulcer includes alleviation of shock, correction of electrolyte abnormalities, and relief of pain. Nasogastric suction is one of the mainstays of treatment. If Non-operative management is considered, the tube should be placed in the most dependent part of the stomach under fluoroscopic control. Parenteral broad-spectrum antibiotics, to cover both aerobes and anaerobes, are also necessary. Finally, eradication of Helicobacter pylori should be considered in all patients. __________________________________________________Section 4 Drugs used in management of Ulcers: Ulcer healing drugs are classified into: 4.1) Neutralizing agents: 4.1.1 Antacids 4.2) Antisecretory agent : 4.2.1 Histamine H-2 receptor blockers 4.2.2 Gastric acid proton pump inhibitors. 4.2.3 Selective Antimuscarinic agent ex, prienzepine and Tricyclic antidepressants. THESE ARE NO LONGER USED 4.3) Mucosal protective agents: 4.3.1 Chelate and Complexes 4.3.1.1 Sucralfate 4.3.1.2 Colloidal Bismuth Compounds: 4.3.2Carbenoxolone 4.3.3 Prostagladin analogue. 4.1) Neutralizing agents: 4.1.1 Antacids A) Mechanism of action. Gastric antacids are weak bases that react with gastric hydrochloric acid to form a salt and water. Their usefulness in peptic ulcer disease appears to lie in their ability to reduce gastric acidity and, since pepsin is inactive in solutions above pH 4.0, to reduce peptic activity. B) Clinical uses of Antacids: After a meal, gastric acid is produced at a rate of about 45 meq/h. A single dose of 156 meq of antacid given 1 hour after a meal effectively neutralizes gastric acid for 2 hours. A second dose given 3 hours after eating maintains the effect for over 4 hours after the meal. The dose response relationship of antacids is variable, depending on the gastric secretary capacity (some individuals are “hyper secretors,” and some “hyposecretors” and the rate at which the antacid is emptied from the stomach. Antacids can be effective as per oral (PO) for symptomatic relief of indigestion, non ulcer dyspepsia, epigastric pain in PUD or heart burn in gastroesophageal reflux disease. C) Dosage: In the best-controlled trial of duodenal ulcer therapy that would maximally neutralize gastric acid throughout a 24-hour period, 140 meq of liquid antacid given 1 and 3 hours after each meal and at bedtime accelerated the healing of duodenal ulcers. Additional doses may be required up to once an hour. Different dosage of antacid is required to achieve this degree of neutralizing capability, depending on the commercial product used. Missed Doses: If your health care practitioner has told you to take this medicine on a regular schedule and you miss a dose, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and return to your usual dosage schedule. Do not double doses. Dosage forms: 1) Chewable tablets and capsules antacids are generally weak in their neutralizing capability, and a large number of tablets would be required for this high-dose regimen. They are not recommended for the treatment of active peptic ulcer. 2) Oral suspensions, liquid. 3) Oral powder D ) Pharmacokinetics. Onset and duration. Onset of acid neutralizing is immediate: duration is 30 10 min in the fasted state and 1-3 hr if ingested after meals. Fate. Antacid cat ions are absorbed to varying degrees. Sodium is highly soluble and readily absorbed; calcium absorption is generally less than 30%, but may decrease with increasing age, intake, achlorhydria, and estrogen loss at menopause; magnesium is generally about 30 % absorbed, but percent absorption may vary inversely with intake; aluminum is slightly absorbed. Calcium, magnesium and aluminum are excreted renally with normal renal function. The unabsorbed portion is excreted in the feces. E) Adverse Reactions and Precautions Long term use of sodium –or calcium- containing antacids can cause systemic alkalosis and fluid retension. Hypercalcemia may occur with ingestion of large amounts of calcium carbonate; soluble antacids plus a diet high in milk products may result in milkalkali syndrome, which can lead to nephrolithiasis It also may cause stone kidney, muscle calcification. Magnesium-containing antacids cause a dose-related laxative effect; hypermagnesemia occurs in patients with renal impairment. Aluminum-containing antacids cause dose-related constipation, especially in elderly. Prolonged administration or large dosages of aluminum hydroxide or carbonate can result in hypophosphatemia, particularly in the elderly and in alcoholics; encephalopathy has been reported in dialysis patients receiving aluminum-containing antacids alone or with sucralfate. Precautions. Avoid magnesium-containing products in renal impairment .Use others with caution in patients with chronic renal failure or with fluid retention avoid those containing large amounts of sodium, e.g magnesium trisilicate mixture (Gaviscon), hypertension, or CHF. Because antacids are particulate and elevate intragastric pH. Caution is recommended also in patients having appendicitis, gastrointestinal bleeding, ulcerative colitis, or intestinal obstruction. F) Drug interactions. Antacids reduce the absorption of numerous drugs, the most important of which are digoxin, oral iron (calcium carbonate, sodium bicarbonate, and possibly magnesium trisilicate), isoniazide (aluminum containing), ketoconazole, oral quinolones, and oral tetracyclines (di -and trivalent cations). Antacids may reduce salicylate levels and increase quinidine levels because of urinary pH changes. Large dosages of calcium antacids may produce hypercalcemia in the presence of thiazides. Sodium polystyrene sulfonate resin can bind magnesium and calcium ions from the antacid in the gut , resulting in systemic alkalosis. G). Patient instruction: If the antacids do not relieve symptoms of indigestion, upset stomach, or heart within 2 weeks, contact your health care practitioner. Diarrhea may occure with magnesium, therefore decrease the daily dosage, alternate dose with or switch to aluminum containing antacids. Refrigerating liquid antacids may improve their palatability. Antacids may interfere with other medications, therefore take other medications 1-2 hours before or after antacids unless, otherwise directed. If tablets are used chew throughout before swallowing and follow with a glass of water. Parameters to Monitor. Monitor for relief of dyspepsia, epigastric pain or heartburn and diarrhea or constipation. Monitor serum phosphate during long-term use of aluminum –containing products in patients with chronic renal impairment. Monitor for drug interactions Notes. Aggressive antacid therapy is at least as effective as the H2-receptor antagonists or sucralfate when treating PUD or preventing stress related mucosal bleeding; however do not use antacids as first line agents because large, frequent doses are inconvenient and associated with an increased risk of adverse effect. Magaldrate is a chemical mixture of magnesium and aluminum hydroxides. Although gastrin is stimulated by calcium, gastric acid rebound with calcium containing antacids is of questionable clinical importance. Activated dimeticone (simethicone) is added to an antacid since its highly effective antiflatulent that act as dispersant of gas bubbles by reducing surface tension destroying there by mucosal pockets of trapped gas, which causes distress. Aliginates added as protectants against gastro-oesophageal reflux disease. H) Trade names: Non proprietary Aluminum –magnesium hydroxide Aluminum – magnesium and simethicone Sodium carbonate 4.2Gastric antisecretory drugs: 4.2) Antisecretory agent: 4.2.1. Histamine H-2 receptor blockers Proprietary name Maalox, Mucogel, Maalox plus Moxal plus Roaids. A) Regulation of Acid secretion: Gastric acid secretion is produced in connection with meals, very weak during inter digestive states; it is strongly stimulated by food uptake and even before, by anticipation of this uptake. This anticipation is due to the existence of a “cephalic phase” which integrates a variety of factors including metabolic stimuli whose effects are either orexigenic, such as hypoglycemia, or anorexigenic (satiety signals). This phase involves central nuclei (mainly the vagus nerve dorsomotor nucleus and the tractus solitaries nucleus). Gastric emptying by food stimulates acid secretion by a local reflex initiated by stomach distention. Gastrin secretion is activated by vagal stimulation and by luminal peptones and amino acids. Then, acid secretion progressively decreases because of the distension of the fundus, which provokes a central inhibitory reflex, of the acidification of the antral lumen, which inhibits gastrin secretion, and of the arrival of nutrients into the intestine, which stimulates the release of inhibitory peptides. Parietal cell receptors: A histaminic H2-receptor is located at the basolateral membrane of the parietal cell . Binding of histamine to the H2- receptor activates adenylate cyclase and thereby CAMP production , via a stimulatory GTP dependent protein. Also the parietal cell basolateral membrane also contains a muscarinic M3 (acetylcholine ) and a gastrin receptor .These two receptors cause an increase in cytosolic Ca+2 concentration which through hydrolysis of membrane phosphoinositides also leads to production of acid.The final common pathway is through the Proton pump H+/K+ ATPase. Inhibitors of the activities of the first two secretagogues and of the proton pump have been developed. H2 - Receptor Antagonists : B) Mechanism of action: The four drugs used are Cimetidine, Ranitidine, and Famotidine and Nizatidine. These agents are capable of over 90% reduction in basal, food stimulated, and nocturnal secretion of gastric acid after a single dose. By competitively and reversibly binding to the H2- Receptors on the parietal cell, diminishing cytosolic cyclic AMP production and secretion of histamine stimulated gastric acid. An interaction between the cyclic AMP and calcium pathways also results in partial inhibition of acetylcholine and gastrin stimulated acid secretion. C) Clinical Use: Many trials have demonstrated their effectiveness in promoting the healing of duodenal and gastric ulcers and preventing their recurrence .In patients with (GU) they are usually given for 8 weeks. In addition they are important in the medical management of Zollinger –Ellison syndrome and gastric hypersecretory states seen in systemic mastocytosis. D) Dosage: Suppression of nocturnal acid secretion appears to be the most important determinant of the rate of healing of duodenal ulcers. For active ulcers, Cimetidine (least potent) can be given in Adult (oral) doses of 400-600 mg twice daily (with breakfast) or 800 mg at bedtime (benign gastric and duodenal ulceration) for at least 4 weeks. (6 weeks in gastric ulceration, 8 weeks in ulcer associated with continued NSAID). Children over 1 year, 25-30mg/kg daily in divided doses. In slow intravenous infusion 200 mg given over at least 5 minutes; may be repeated every 4-6 hours Ranitidine and nizatidine can be given in Adult (oral) dosage of 150 mg twice daily or 300 mg at night (benign gastric and duodenal ulcerations) for 4 to 8 weeks (more potent) maintenance therapy therapy of 150 mg at night. For child (peptic ulcer) 2-4 mg/kg twice daily. By intravenous infusion for short –term use in peptic ulcer hospital inpatients as alternative to oral route in ranitidine give 50mg diluted to 20 ml, and given at least 2 minutes; in nizatidine 10 mg / hour, not recommended in child. Famotidine (most potent) can be given at 20 mg (orally) daily as maintenance therapy at bedtime or 40 mg at night for 4-8 weeks. Child it is not recommended. Dosage forms: 1) Capsules, tablets 2) Syrup, suspension. 3) Effervescent tablets 4) Injection (IM, IV infusion). Dosage: Indication PO for short term ttt of active duodenal ulcer (4-8 weeks) PO for maintenance of healed duodenal ulcer PO for short term ttt of active benign gastric Cimetidine 300 mg qid. 400mg bid Famotidine Nizatidine 20 mg bid or 150 mg bid 40 mg hs or 300 mg hs Ranitidine 150 mg bid or 300 mg hs 400 mg hs 20 mgs hs 150 mg hs 150 mg hs 300 mg qid 20 mg bid or 150 mg bid or 800 mg hs 40 mg hs or 300 mg hs 150 mg bid or 300 mg hs ulcer (6-8 weeks) PO for maint. Healed of GU 400 mg hs 20 mg hs 150 mg hs 150 mg hs Missed Doses; If you miss a dose, take it as soon as possible .If it is almost time for your next dose, skip the missed dose and return to your usual dosage schedule. Do not double doses. E) Patient Instructions. Cigarette smoking may decrease the effectiveness of H2-Receptor antagonists in peptic ulcer disease. Discontinue or decrease smoking or avoid smoking after the last dose of the day, since ulcers will fail to heal with 4 weeks of conventional therapy. Antacids may be used as needed for relief of epigastric pain. Even though ulcer symptoms may improve, continue treatment for the duration of therapy unless instructed otherwise. If symptomatic relief is not obtained in 2 weeks with over the counter medication, contact you health care practitioner. Report any bleeding, vomiting, or sever esophageal or abdominal pain. Take tablet or liquid, swallow with liquid. Parameters To Monitor: Improvement in epigastric pain or heartburn. In patients receiving IV doses of cimetidine (2.4g/day) or ranitidine (400 mg/day), it is advisable to monitor serum transaminases routinely throughout the duration of IV therapy. Measure the intragastric pH periodically and monitor for potential drug interactions. F) Clinical Uses: Indications systemic mastocytosis, Zollinger-Ellison syndrome, aspiration prophylaxis, duodenal ulcer, dyspepsia, esophagitis, gastric ulcer, gastroesophageal reflux disease (GERD), Helicobacter pylori multiple endocrine adenoma syndrome, NSAID-induced ulcer prophylaxis pyrosis, (heartburn) stress, gastritis prophylaxis. G) Pharmacokinetics : Onset; all agents have an oral onset of 1 hour and an IV onset of 15 min. Cimetidine Famotidine 41 4% ug/L 70 5 % Fate oral 60 20 % bioavailablity ug/L Excreted 75% unchanged in urine T.5 normal 1.9 0.4 hr 3 0.5 hr T.5 anuric 20 + hr 4.5 0.5 H) Adverse reactions and Precaution : Nizatidine Ranitidine 95 5%; 75 % 55 25 % ug/L failure 70% 70 5 % 1.4 0.2 hr 7.2 1.3 hr 2 0.4 hr 7 3 hr In general the H2-receptor antagonist are safe and well tolerated, when used in recommended therapeutic doses for the treatment of PUD.Adverse reactions are generally mild. The most frequent adverse events occur in 1-7% of patients and include, headache, diarrhea, constipation, dizziness, drowsiness and fatigue. Reversible confusional states, depression, agitation and other CNS manifestations may occur occasionally.Rare cases of fatal hepatic disease with and without jaundice have been reported with cimetidine and ranitidine. Cardiac arrhythmias, tachycardia, and hypotension may occur following rapid IV bolus administration of cimetidine or ranitidine, bradycardia with both oral and IV administration of these drugs. Negative inotropic effect has been noted following oral administration of famotidine in healthy subjects and patients with CHF. Hematological reactions occur occasionally with all H2 receptor antagonists, and include leukopenia, neutropenia, thrombocytopenia and they may cause mild but reversible increase in fasting serum gastrin. Gynecomastia develops in less than 1% of all men receiving cimetidine , but in 4% of men treated for pathologic hypersecretory states as a long prolonged high dose treatment. Dose dependent increases with serum prolactin concentrations with cimetidine and ranitidne. Hyperuricemia with nizatidine.. Ranitidine and cimetidine may cause alopecia. Precautions: Pregnancy, lactation, dosage adjustment may be required in severe renal and /or hepatic failure. H2-receptor antagonist may mask symptoms of gastric cancer; particular care is required in those whose symptoms change and in those who are middleaged or over. Don’t take it if you are allergic to H2-receptor antagonist. I) Drug interactions: The potential drug interactions exist with the entire H2-receptor antagonist, they may: 1) Alter the bioavailablity of orally administered drugs as a consequence of increating intragastric pH.ex ketoconazole. 2) They bind reversibly to hepatic cytochromes P450 and decrease the hepatic clearance of drugs that undergo phase I metabolism of ethanol. 3) Inhibit gastric mucosal alcohol dehydrogenase thereby influencing the mucosal metabolism of ethanol. 4) Decrease the renal clearance of drugs by inhibiting their renal tubular secretion. Numerous drug interactions has been reported with cimetidine, important drug interaction exist with drugs of narrow therapeutic index e.g. (theophyline, phenytoin, warfarin), metabolic interaction with cimetidine may be dose dependent. Antacids Decreases absorption of ranitidine if taken simultaneously. Famotidine and nizatidine no effect on hepatic drug metabolism. Possible Interaction With Other Substances: Interacts Combined effect with Alcohol Caffeine drinks Food Tobacco No interaction expected, but alcohol may slow body’s recovery. Best to avoid May increase acid secretion and delay healing Enhanced effectiveness, protein rich foods should be water in moderation to minimize secretion of stomach acid. Reverses cimetidine effect. Tobacco may slow body’s recovery. Best to avoid it. Notes: In general, the H2- receptor antagonists are similar in efficacy when conventional dosages are prescribed for the treatment of gastric and duodenal ulcer and for maintenance of healing of duodenal ulcer. The H2 -antagonists is often used in combination with a number of antibiotics to eradicate Helicobacter pylori in peptic ulcer disease. Usual dosages of H2-receptor antagonists are less effective than MISOPROSTOL or proton pump inhibitors in preventing NSAID –induced gastric ulcer. However high doses of FAMOTIDINE may be effective in preventing and healing NSAID-induced gastric and duodenal ulcers. Intermittent admiistration or continuous infusion of IV cimetidine, ranitidine or famotidine is more effective than preventing upper GI bleeding in critically ill patients. J) Trade names: Non Proprietary Name Cimetidine Famotidine Proprietary Name Tagamet , Dyspamet, Apo-Cimetidine , Peptol ,Novocimetidine Pepcid , Famotec Nizatidine Ranitidine Axid Ranitidine, Zantac, Rantag 4.2.2 Proton Pump Inhibitors: A) Mechanism of HCL transport: The parietal cells, located in parietal or oxyntic glands of the gastric fundus and corpus, have been identified as the source of gastric acid secretion .The molecule responsible for secretion, gastric H+,K+-ATPase, or the gastric acid pump, which is found in large quantity only in the gastric parietal cells, uses the chemical energy of ATP to transport hydrogen protons from thecell's cytoplasm into its secretory canaliculi. The outward H+ transport is accompanied by an inward transport of potassium (one H+ for one K+) from the canaliculus. Then K+ and Cl- enter the canaliculi, via either a K+,Cl- transporter or K+ and Cl- channels present in the canaliculi membrane. The pump reabsorbs the K+ in exchange for H+ extrusion. The Cl- accumulates with the H+, resulting in the net secretion of isotonic HCl. B) Mechanism of action of Proton Pump Inhibitors : Proton Pump Inhibitors (PPIs) are inactive substituted benzimidazoles that , when protonated in the secretory canaliculi of the parietal cells forms A sulfhydryl bond which , covalently bind to H+/K+ -ATPase. The PPIs produce a profound and prolonged antisecretory effect that persists for several days and inhibit basal , nocturnal , pentagastrin , and food stimulated gastric acid secretion . Secrum gastrin levels increases during treatment , but return to pretreatment levels within 1-2 weeks of discontinuing therapy. C) Dosage : Indication Lansoprazol Omeprazole PO for short term ttt 15mg/day 20mg/day 15mg/day 20 mg/day PO for reduction of Days 1-10 30mg Days 1-14 40mg bid ,then the risk of DU bid or Days15-28 20 mg ,Or Days 1- of active (DU)(4-8 weeks) PO for maintenance of healed ( DU) recurrence 10 ,40 mg bid then days 11-28 Days 1-14 30 mg , 20 mg/day bid or days 1-14 30 mg bid. PO for short term ttt 30 mg/day 40 mg/day 15-30 mg/day 20-40 mg/day of active benign (GU)(4-8 weeks) PO for maintenance of healed (GU) Pantoprazole IV and oral dosage is 40 mg once daily , dosage reduction is required in hepatic insufficiency. Rabeprazole is a partially reversible H+/K+-ATPase inhibitor given in a dose of 20 mg/day orally. The efficency and tolerability of pantoprazole and rabeprazole are similar to those of omeprazole and lansoprazole . They are not recommended in child. Dosage forms : 1. Omeprazole and lansoprazole are inactivated by gastric acid therefore the drugs are administered orally in capsule , that contains pH-sensitive granules that release the drug when the pH is higher than 6. Upon dissolution of the capsule in the stomach the granules passes into the duodenum where the drug is released and absorbed. In patients who are unable to swallow the capsule , may be opened but the granules should be administered in an acidic juice (orange juice) to avoid dissolution of the protective coating. 2. Pantoprazole is present in the form of Tablets , injection powder for reconstitution. 3. Rabeprazole is present in the form of Tablets. Missed Doses : If you miss a dose , take it as soon as possible .If it is almost time for your next dose , skip the missed dose and return to your usual dosage schedule. Do not double doses. D) Clinical uses : Omeprazole is indicated for short term therapy of gastroesophageal reflux disease, gastric and duodenal ulcers, and gastric hypersecretory conditions including Zollinger-Ellison syndrome, systemic mastocytosis, and multiple endocrine adenoma. Despite its potency, omeprazole must be used in combination with antibiotics to be effective against Helicobacter pylori. E) Patient Instructions : Swallow capsule whole or open the capsule and sprinkle the granules on apple or orange juice , and take before meals. Swallow capsule or intact granules immediately without chewing. The effectiveness of PPIs in peptic ulcer disease may be decreased by cigarette smoking. Even though symptoms may improve , continue treatment for the duration of therapy unless instructed otherwise. Parameters to monitor : Improvement in epigastric pain , or heart burn , however pain relief in peptic ulcer disease does not correlate directly with endoscopic evidence of healing. Monitor for potential drug interactions and adverse effects. Asses the indication , dosage and duration of PPI therapy especially as it relates to the need for treatment beyond 16 weeks. Consider monitoring serum vitamin B12 concentration every several years in patients on long-term PPI therapy. F) Pharmacokinetics : i. Onset and duration . Onset of antisecretory activity after multiple oral daily doses is within 1 hr for all PPIs. Duration of antisecretory effect is dose dependent. Gastric acid inhibition increases with repeated daily doses, reaching a plateau after several days. Gastric secretary activity gradually returns to pretreatment levels 2-5 days after discontinuation. There is not indication that rebound gastric acidity occurs. ii. Serum levels . Antisecretory effects correlates with AUC rather than serum levels. Inhibition of gastric acid secretion continues after serum drug concentration have decrease below the limit of detection, apparently caused by prolonged drug binding to parietal cell H+/K+-ATPase. Fate Lansoprazole Omeprazole Pantoprazole Oral bioavailability 80% 65% 77% Protein binding 97% 95% 98% Excreted unchanged in urine Very little Very little Very little t.5 healthy young adults 1.50.2 hr 0.75 0.25hr 0.662.06 t.5 healthy elderly 2.2 0.7 hr 1 hr 1.64 hr G) Adverse reaction and Precaution: The short and long term safety of lansoprazole appears to be similar to that of omeprazole. Headache ,diarrhea , nausea , and dizziness , occur frequently. Constipation , fatigue malaise , muscle cramps , Stevens-Johnson syndrome, joint pain , myalgia , anxiety , skin rash , and taste perversion occur occasionally. Rarely gynecomastia , hemolytic anemia , thrombocytopenia , and psychic disturbances have been reported. Rare cases of skin reactions overt hepatic failure , liver necrosis , pancreatitis , interstitial nephritis and agranulocytosis have occurred with omeprazole .Rarely gastric polyposis has occurred in patients receiving 20-24 mg of omeprazole for 12 months or longer. Long term PPI use may reduce the absorption of protein bound vitamin B12.Adverse effects in patients over 65 years of age are similar to that of younger patients. Pantoprazole also causes fever , liver enzyme changes and raised triglycerides. Precautions : Pregnancy , breast feeding , they should be used in caution with in patients with liver disease since clearance of the drug can be prolonged. Proton pump inhibitors may mask symptoms of gastric cancer particular care is required in those whose symptoms change and in those over 65 years of age. Should not use PPIs in patients who are hypersensitive to such product. H) Drug interactions: Elevations in gastric pH could increase the extent of absorption of ampicillin , and decease the rate of extent of absorption of digoxin, itraconazole , iron salts, ketoconazole, and other drugs or dosage forms that are pH dependent. Omeprazole pantoprazole interacts selectively with hepatic enzyme , and may inhibit the metabolism of drugs , such as some benzodiazepines (e.g. .diazepam), carbamezapine , cyclosporins , phenytoin , and warfarin . They increase the hepatotoxicity of acteominophen or lead to an increased risk of cancer in smokers. Lansoprazole they may increase theophylline clearance. Possible interactions with other substances : Interacts with Combined effect Alcohol Decreased effect Caffeine drinks Decreased effect Spicy food Decreased effect Tobacco Decreased effect Notes : The PPIs are effective in preventing NSAID-induced gastric and duodenal ulcers and appear to be superior to Misoprostol 200mg bid or ranitidine 150mg bid.When prophylactic treatment with omeprazole 20 mg/day was compared with misoprostol 200 bid , omeprazole was associated with a lower relapse rate and was better tolerated than misoprostol. Coadminstration of PPI with an H2 receptor antagonist is without established benefit , the action of PPI many be compromised if administered .PPIs are more cost effective than the h2 receptor antagonists when treating patients with severe ulcers. I) Trade names: Non Proprietary name Omeprazole Lansoprazole Pantoprazole Rabeprazole sodium Proprietary name Losec®, Prilosec® Risek® Heliclear®, Prevacid®, Pantozol® Pariet® 4.3 Mucosal Protective agents : 4.3.1 Chelate and Complexes 4.3.1.1 Sucralfate A) Mechanism of action : Sucralfate is an aluminum hydroxide salt of a sulfated disaccharide. It is only minimally absorbed 3-5% from the GI tract. When exposed to acid , the sucralfate forms a viscous adhesive that binds electrostatically to positively charged protein molecules in the ulcer crater, forming a protective barrier that inhibits the back diffusion of hydrogen ions, pepsin and bile salts. Adherence to the ulcer crater is enhanced at a pH 3.5 and it lasts for up to 6 hours following oral administration. Sucralfate inhibits pepsin , adsorbs bile salts , stimulates endogenous Prostaglandin’s and EGF. Sucralfate does not have an action on the acid secretion. B) Dosage : PO for short term treatment of DU 1g qid on an empty stomach, 1 hr before meals and at bedtime or 2g bid for 4-8 weeks. PO for maintenance of healed DU 1g bid. PO for short-term treatment of active benign gastric ulcer 1g qid. Dosage forms : 1. Tab 1g 2. Susp 100mg/ml Missed doses : If you miss a dose , take it as soon as possible .If it is almost time for your next dose , skip the missed dose and return to your usual dosage schedule .Do not double doses. C) Patient instructions : Take this drug with water on an empty stomach , 1 hour before each meal and at bedtime. Antacid may be used as needed for pain relief , but DO NOT take them within 30 minutes before or after sucralfate. Since they require an acid pH to be activated and so should not be administered with antacid or H2-antagonist.Take potentially interacting drugs 2 hours before sucralfate in order to avoid or minimize drug interactions. Even though symptoms may decrease , continue treatment for the duration for therapy unless instructed otherwise. Parameters to monitor : Improvement in epigastric pain or heart burn . Observe for constipation and signs of aluminum toxicity in the elderly , in chronic renal failure , or in patients , receiving other aluminum-containing drugs.Obtain serum phosphate, periodically, in patients , receiving concurrent aluminum-containing drugs or with prolonged use.Monitor for potential drug interactions. D) Pharmacokinetics : Onset and Duration : Onset (attachment of sucralfate to ulcer site) is within 1 hr , duration is about 6 hours.Fate , sucralfate is only minimally absorbed from the GI tract and is excreted primarily in the feces. About 3-5% (primarily aluminum) is absorbed and excreted in E) Adverse reaction and Precaution : Adverse reaction are usually minor and occur in about 5% of patients. Constipation occurs in about 2% of patients. Other effects , including diarrhea, nausea , gastric discomfort, indigestion , dry mouth , rash , pruritus ,backache , dizziness , drowsiness, vertigo , and a metallic taste occur occasionally .Aluminum accumulation and toxicity , including osteodystrophy , osteomalacia , encephalopathy , and seizures, have been reported in patients with chronic renal failure. Hypophosphatemia may develop in critically ill patients and those on prolonged sucralfate therapy. Precautions :Use with caution in patients receiving other aluminum-containing drugs or in chronic renal failure and dialysis. F) Drug interactions : Sucralfate may inhibit the absorption of drugs including digoxin , ketoconazole , levothyroxine , phenytoin, quinidine, oral quinolones, tetracyclines, theophylline and warfarin. In most cases these interaction can be avoided if the drug is given 2 hr before sucralfate administration. Notes : Sucralfate may overcome the negative effect of cigarette smoking on DU healing and recurrence.It is effective in preventing stress-related mucosal bleeding .It is poorly absorbed systemically (though risking blood levels have been documented in patients with renal failure). G) Trade names: Non Proprietary name Proprietary name Sucralfate Antepsin® Carafate® 4.3.1.2 Colliodal Bismuth Compounds : A) Mechanism of action : Bismuth salts are used to treat nausea , indigestion , diarrhea , gastritis and peptic ulcers . They cause local gastroprotective effect , stimulation of endogenous prostaglandins , and antimicrobial activity against Helicobacter pylori.Given alone , bismuth salts suppress H.pylori but long term eradication requires combination therapy with antibiotics.Bismuth subsalicylate is the bismuth salt used often and Ranatidine bismuth citrate is a complex of ranitidine trivalent bismuth , and citrate. B) Dosage : PO for the control of nausea , abdominal cramps , and diarrhea 52.5mg qid to maximum of 4.2 g/day.When given with antibiotics to eradicate H.pylori treatment is usually limited to 1-2 weeks. Dosage Forms: 1) Suspension of (Bismuth subsalicylate) 17.5,35 mg/ ml 2) Tab (ranitidine bismuth citrate (RBC ) 262 mg Tab 400 mg (containing ranitidine 150 mg and bismuth citrate 240 mg) C) Pharmacokinetics: Following oral administration , BSS(58% bismuth , 42% salicylate) is converted in the GI tract to bismuth oxide and salicylic acid. Bismuth is less than 0.2% absorbed with more than 99% of an oral dose excreted in feces. Over 90% of the salicylate dose is absorbed and excreted in urine. Ranitidine bismuth citrate (RBC) dissociates in intragastric fluid to ranitidine and soluble and insoluble forms of bismuth. Oral absorption of bismuth from (RBC) is variable. D) Adverse reactions: BSS and bismuth derived from RBC may cause temporary darkening of the tongue and stool .Use BSS with caution in children , in the elderly , in patients with renal impairment , salicylate sensitivity or bleeding disorders , in those receiving high-dosage salicylate therapy, or when potentially interacting medications are taken. Salicylic acid is less likely than aspirin to cause gastric mucosal damage and blood loss. Prolonged BSS therapy and the use of other salts have been associated with neurotoxicity.Bismuth concentrations may be elevated in the elderly and patients with renal impairment because of decreased renal elimination. RBC should not be used as a single agent for the treatment of active duodenal or gastric ulcers. E) Uses: They are used in GU and DU and for eradication therapy in Helicobacter pylori as a combination therapy with antibiotics. F)Trade names: Non proprietary name Proprietary name Tripotassium dicitratobismuthate De-Noltab , Tritec 4.3.2 Carbenoxolone: A) Mechanism of action: It is a synthetic derivative of glychrihizic acid (an agent extracted from liquorice) .The mechanism of action of not clear but it is thought to involve an increase in the production, secretion, and viscosity of intestinal mucus. B) Dosage Forms: 1) 2) Tablets, chewable Liquid Dosage: 1 tablet to be chewed 3 times daily after meals, and 2 at night for 6-12 weeks or 10 ml liquid 3 times daily after meals and 20 ml at night for 6-12 weeks. C) Adverse reactions and Precautions It has major aldosterone- like side effect, hypertension, fluid retention and hypokalemia which has limited its clinical usefulness. Muscle weakness, cardiac failure. Precautions : In cardiac disease, hypertension, hepatic and renal disease, elderly over the age of 75 years. NOT recommended for children. D) Drug Interactions: The concurrent administration of spironolactone controls the fluid retention but also abolishes the ulcer healing effect; the thiazide prevents sodium retention without abolishing the beneficial effect in peptic disease. E) Parameters to measure: If it is used regular monitoring of weight, blood pressure, and electrolytes is advisable during treatment. F) Uses: It is used for both DU and GU. G) Trade name: Non-proprietary name Proprietary name Carbenoxolone sodium Pyrogastrone® 4.3.3 Prostaglandins analogues: A) Mechanism of action: Misoprostol is a synthetic prostaglandin E1 analogue that inhibits gastric acid secretion and enhances gastric mucosal defense. Antisecretory effect occur at doses of 200ug or more .The gastric ulcer protective effect of misoprostol appears to plateau between 200ug bid-tid, but no dose-response effect is apparent in preventing duodenal ulcer. B) Dosage: PO for GI protection during NSAID therapy, 200ug qid with food, if this dosage is not tolerated, and 100-ug qid can be used. Lower-dosage regimens of misoprostol 200 ug tid or bid appear similar in efficacy and better tolerated for protection against NSAIDinduced gastric and duodenal ulcers than 200 mg qid dosage. Dosage reduction is not required in renal impairment, hepatic failure, or in the elderly. Dosage Forms: 1) Tab 100, 200ug. Misoprostol is also available in combination with diclofenac in Arthrotec. Missed Dose: Take as soon as you remember up to 2 hours late. If more than 2 hours, wait for the next scheduled dose (don’t double this dose). C) Pharmacokinetics: After oral administration, misoprostol is extensively absorbed and rapidly de-esterified to the active drug, misoprostol acid. Peak serum concentrations of misoprostol acid are reduced when the drug is taken with food. Plasma protein binding of misoprostol acid <90%. Misoprostol acid undergoes further metabolism, but approximately 80% is excreted unchanged in urine. D) Adverse reactions: Diarrhea is reported to occur within 2 weeks of initiating therapy in 14-40% of patients on NSAIDS receiving 800 ug/day, and less frequently with 400-600ug/day. Diarrhea is usually self-limiting and resolves in about 1 week with inflammatory bowel disease. Abdominal pain occurs in 13-20% of patients on NSAIDs receiving Misoprostol 800 ug/day. Antacids (except those containing magnesium) may be used for abdominal pain relief. Nausea, flatulence, headache, dyspepsia, vomiting, and constipation occur occasionally. Women who receive misoprostol occasionally develop gynecological disorders including cramping, or vaginal bleeding. Precautions: It is contraindicated in pregnancy because of high risk of abortion. Warn patients not to give Misprostol to other. Advise patients receiving concurrent corticosteroids or anticoagulants, to report bleeding vomiting, severe abdominal pain, and diarrhea. E) Drug interactions : Misprostol does not affect the hepatic cytochrome P450 microsomal enzyme system, nor does it interfere with the beneficial effects of NSAIDs in rheumatoid arthritis. Possible Interaction With Other Substances: Interacts with Alcohol Caffeine Tobacco Combined effect Decreases misoprostol effect. Avoid Decreases misoprostol effect. Avoid Decreases misoprostol effect. Avoid F) Patient instructions: The tablets swallow with liquid .If you can’t swallow whole, crumble tablet and take with liquid or food. Take on empty stomach mean 1 hour before or 2 hours after eating. G)Clinical uses: Prevents development of stomach ulcers in persons taking nonsteroidal, antiinflammatory analgesic (NSAID’s), including asprin. H)Trade names: Non proprietary name Preparatory name Misoprostol Cytotec® __________________________________________________Section 5 5.1 The role of Helicobacter Pylori: A) Introduction: Associations are now established with chronic atrophic gastritis, peptic ulcer, and Helicobacter pylori. The organism's effect apparently reflects its ability to induce a chronic inflammatory response, which can result in gastric or duodenal ulceration and, in some susceptible individuals, to gastric carcinoma. Helicobacter pylori, whose only natural host is the human, is restricted mainly to the gastric antral surface, where a number of specialized virulence (maintenance) factors allow it to flourish, while causing minimal harm to its host. B) What are Helicobacter pylori? Helicobacter pylori (H. pylori) are a spiral-shaped bacterium that is found in the gastric mucous layer or adherent to the epithelial lining of the stomach. H. Pylori causes more than 90% of duodenal ulcers and up to 80% of gastric ulcers. He majority of patients were given long-term medications, such as H2 blockers, and more recently, proton pump inhibitors, without a chance for permanent cure. These medications relieve ulcer-related symptoms, heal gastric mucosal inflammation, and may heal the ulcer, but they do NOT treat the infection. When acid suppression is removed, the majority of ulcers, particularly those caused by H. pylori, recur. Since we now know that most ulcers are caused by H. pylori, appropriate antibiotic regimens can successfully eradicate the infection in most patients, with complete resolution of mucosal inflammation and a minimal chance for recurrence of ulcers. Pathogenesis: Once H. pylori is safely ensconced in the mucus, it is able to fight the stomach acid that does reach it with an enzyme it possesses called urease. Urease converts urea, of which there is an abundant supply in the stomach (from saliva and gastric juices), into bicarbonate and ammonia, which are strong bases. This creates a cloud of acid neutralizing chemicals around the H. pylori, protecting it from the acid in the stomach. The reaction of urea hydrolysis (urea is broken down to ammonia and carbon dioxide) is shown below. This reaction is important for diagnosis of H.pylori by the breath test. C=O (NH2) 2 + H+ + 2H2O ---urease---> HCO3- + 2(NH4+) Another defense H. pylori has is that the body's natural defenses cannot reach the bacterium in the mucus lining of the stomach. The immune system will respond to an H. pylori infection by sending white cells, killer T cells, and other infection fighting agents. However, these potential H. pylori eradicators cannot reach the infection, because they cannot easily get through stomach lining. They do not go away either, though, and the immune response grows and grows. Polymorphs die, and spill their destructive compounds (super oxide radicals) on stomach lining cells. Extra nutrients are sent to reinforce the white cells, and the H. pylori can feed on this. Within a few days, gastritis and perhaps eventually a peptic ulcer results. It may not be H. pylori itself which causes peptic ulcer, but the inflammation of the stomach lining; i.e. the response to H. pylori. C) Prevalence: The rate of infection increases with age, so it occurs more often in older people. H.pylori affects about 20% of persons below the age of 40 years, and 50% of those above the age of 60 years. H.pylori is uncommon in young children. Low social-economic status predicts H.pylori infection. Immigration is responsible for isolated areas of high prevalence in some Western countries. In developing countries most adults are infected. The majority of duodenal ulcers (> 90%) are caused by H.pylori. Non-H. Pylori duodenal ulceration is generally the result of Zollinger-Ellison (ZE) syndrome or, less often, of NSAID use. Acquisition occurs in about 10% of children per annum between the ages of 2 and 8 years so that most are infected by their teens. D) Detection of Helicobacter pylori: [Laboratory Tests] Who should be tested for H. pylori ? Persons with active gastric or duodenal ulcers or documented history of ulcers should be tested for H. pylori, and if found to be infected, they should be treated. To date, there has been no conclusive evidence that treatment of H. pylori infection in patients with nonulcer dyspepsia is warranted. Testing for and treatment of H. pylori infection are recommended following resection of early gastric cancer and for low-grade gastric MALT lymphoma. Retesting after treatment maybe prudent for patients with bleeding or otherwise complicated peptic ulcer disease. Treatment recommendations for children have not been formulated. A specialist should evaluate pediatric patients who require extensive diagnostic work-ups for abdominal symptoms. Helicobacter pylori can be detected by one of three different tests: 1) Blood tests / Serology (Blood tests such as the enzyme-linked immunosorbent assay (ELISA) and quick office-based tests identify and measure H. pylori antibodies. The body produces antibodies against H. pylori in an attempt to fight the bacteria. The advantages of blood tests are their low cost and availability to doctors. The disadvantage is the possibility of false positive results in patients previously treated for ulcers since the levels of H. pylori antibodies fall slowly. 2) Urea- Breath tests (UBT), it measure carbon dioxide in exhaled breath. Patients are given a substance called urea with carbon to drink. Bacteria break down this urea and the carbon is absorbed into the blood stream and lungs and exhaled in the breath. By collecting the breath, doctors can measure this carbon and determine whether H. pylori is present or absent. Breath tests are highly specific (98%) and very sensitive (95%). They can indicate eradication of H. pylori 4 weeks after antibiotic treatment, at a time when antibody tests will still read positive. 3) Saliva Test which is not generally available, rapid tests using salivary and /or gingival IgG and IgA secretions have been evaluated for detection of H. pylori. Less accurate than the best serum ELISA methods, these tests may be equal to rapid office tests, are simpler, and may be particularly appropriate for children 4) The final method of detecting H. pylori by tissue test or what is known as Endoscopy based test, (a visual exam of the stomach through a thin, lighted, flexible tube), the physician can remove small bits of tissue from the stomach wall through the tube. The tissue can then be examined under a microscope for the presence of H. pylori by campy lobacter-likeorganism (CLO) test. A major advantage of endoscopy is its capacity to detect also mucosal lesions, such as gastritis and duodenitis There are three types of test for detection: 1) The rapid urease test detects the enzyme urease, which is produced by H. pylori. 2) A histology test allows the doctor to find and examine the actual bacteria. 3) A culture test involves allowing H. pylori to grow in the tissue sample. E) Causes of Helicobacter pylori: H. Pylori are believed to be transmitted orally. Many researchers think that H, pylori is transmitted orally by means of fecal matter through the ingestion of waste tainted food or water. In addition, it is possible that H. pylori could be transmitted from the stomach to the mouth through gastro-esophagal reflux (in which a small amount of the stomach's contents is involuntarily forced up the esophagus) or belching, common symptoms of gastritis. The bacterium could then be transmitted through oral contact. Iatrogenic spread through contaminated endoscopes has been documented but can be prevented by proper cleaning of equipment. F) Eradication therapy of Helicobacter Pylori: The short-term goals of peptic ulcer therapy are to resolve symptoms and heal the ulcer. The long-term goal is to prevent recurrence, thereby reducing morbidity, mortality, and health-care cost. With the discovery and elucidation of the causativerole of Helicobacter pylori in peptic ulcer disease and the development of treatments that eradicate the organism, the disease can now be cured. When should H.pylori infection be treated? All patients with proven gastric or duodenal ulcers who are infected with H.pylori. Patients with previously proven recurrent duodenal ulcers who are currently requiring maintenance anti ulcer therapy. For management of the small number of peptic ulcers in children a definitive endoscopic and microbiological diagnosis is advisable. G) How are H. pylori Peptic Ulcers treated? H. Pylori peptic ulcers are treated with drugs to kill the bacteria, to reduce stomach acid, and to protect the stomach lining. Antibiotics are used to kill the bacteria. Treatment usually involves a combination of antibiotics, acid suppressors, and stomach protectors. Three-drug regimens that contain a Proton Pump inhibitor plus two antibiotics may be taken for 7 to 10 days rather than 14days to minimize adverse effects and enhance compliance, however eradication rates may be lower, especially with the 1-week regimen. Four –drug regimens of bismuth subsalicylate, metronidazole, and tetracycline or amoxicillin and an antisecretory drug are effective and have lower drug cost, but are associated with a high frequency of adverse effect (up to 70%) and medication noncompliance. Unfortunately, patients may find triple therapy complicated because it involves taking as many as 20 pills a day. Also, the antibiotics used in triple therapy may cause mild side effects such as nausea, vomiting, diarrhea, dark stools, and metallic taste in the mouth, dizziness, headache, and yeast infections in women. (Most side effects can be treated with medication withdrawal.) An antisecretory drug should be included when the patient has an active ulcer in order to provide rapid relief of symptoms and enhance ulcer healing . Extending antisecretory drug therapy beyond the 7-14 days of antimicrobial therapy should be considered in ulcer patients with a history of ulcer complication who remain symptomatic upon cessation of the antimicrobial regimen. The selection of the eradication regimen should be individualized and based on efficacy, tolerability, drug interaction potential, antibiotic resistance, cost and the likelihood of compliance. Antibiotics should not be used for longer than 2 weeks. If treatment fails a different antibiotic regimen should be considered. NOTE that: ampicillin should not be substituted for amoxicillin, doxycycline should not be substituted for tetracycline, an H2-antagonist should not be substituted for a proton Pump inhibitor, and bismuth salts should not be interchanged. When eradicating H.pylori, omeprazole 20 mg and lansoprazole 30 mg are interchangeable. i. Antimicrobial Monotherapy Helicobacter pylori are sensitive to a wide variety of antibiotics in vitro, but not in vivo. Results using single antibiotics have been uniformly disappointing; some antibiotics are inactivated or destroyed at the acid pH of gastric juice, whereas others, such as the nitroimidazoles, which should work at low pH, are ineffective as mono therapy because they induce bacterial resistance. Others suppress but do not eradicate H. pylori. ii. Triple Antimicrobial Therapy: Because of metronidazole's propensity to induce resistant organisms, it is combined with a bismuth compound, which substantially reduces the development of resistance, as well as exerting a direct toxic effect on the organism. Deposition of bismuth into H. pylori's outer membranes and within degraded bacteria causes ultra structural damage within approximately 2hours after dosing with BSS. This triple antibiotic regimen consists of 10 to 14 days of: BSS two tablets qid Metronidazole 250 mg qid The regimen's major disadvantage is the challenge to patient compliance of having to take 16 pills daily for up to 2 weeks. Tetracycline 500 mg qid. iii. Antisecretory/Antimicrobial Therapy : Four antisecretory /antimicrobial regimens designed for both ulcer healing and eradication of H. pylori have been approved. Omeprazole plus clarithromycin Ranitidine bismuth citrate (RBC) plus clarithromycin Bismuth triple therapy plus ranitidine Lanzoprazole plus clarithromycin and amoxicillin. iv. Omeprazole/Clarithromycin: The inclusion of an acid pump inhibitor offers the advantage of: Rapid symptom relief The highest rate of ulcer healing (87% to 100%). v. Ranitidine Bismuth Citrate/Clarithromycin : According to the manufacturer's labeling, the regimen's: H. pylori eradication rates range from 73% to 84% Ulcer healing rates are 71% to 75%. 21% in the RBC/clarithromycin group 40% in the clarithromycin only group 86%, RBC only vi. Bismuth Triple Therapy/Ranitidine: At 6 months—4% for the combination; 85% for ranitidine alone At 12 months—9% vs 95% At 2 years—12% vs 95%. This triple therapy/ranitidine regimen is, to date, the least expensive of the approved antisecretory / antimicrobial combination treatments. H) Dosage: Drugs Dose Frequency Duration Efficacy Side effects Clarithromycin 500mg Bid 10-14 Good- days excellent Medium Metronidazole 500mg Bid Omeprazole 20 mg Bid Clarithromycin 500mg Bid Amoxicillin 1g Bid Omeprazole 20 mg Bid Amoxicillin 1g Bid Metronidazole 500mg Bid Omeprazole 20mg Bid BSS (bismuth) 525mg Qid Metronidazole 250mg Qid Tetracycline 500mg Qid H2antagonist Conventional 10-14 Good- Low- days excellent medium 14 days Good Medium 14 days Good- Medium- excellent high ulcer heal dosage for 28 days Clarithromycin 500mg Tid 14 days Ranitidine 400 mg Bid 28 days Clarithromycin 500mg Tid 14 days Omeprazole Qid Fair – LOW- good medium Fair- LOW – good medium Bismuth chelate NOTE: 40 mg Studies has shown Pantroprazole based simple safe triple therapy with clarithromycin and amoxycillin is more effective than same omeprazole based Triple therapy in H-pylori Eradication, and with appropriate antibiotics is more effective than the quadruple therapy containing Ranitidine, Bismuth and Antibiotic in the Eradication of H-pylori and Healing of Ulcers. Pantoprazole raises the pH 5 for 14.43 hr, and enhances antibiotic efficacy at stable pH 5.Drug interactions with pantoprazole are negligible therefore it can be used instead of omeprazole. I) Patient Instructions: Patient should be instructed to take all their medication (except PPIs) with meals and at bed time (if necessary) , PPIs should be taken prior to eating and a full glass of water should be taken to reduce the potential risk of esophageal irritation and ulceration that may be induced by tetracycline. J) What illness does H.pylori cause ? Most persons who are infected with H. pylori never suffer any symptoms related to the infection; however, H. pylori cause chronic active, chronic persistent, and atrophic gastritis in adults and children. Infection with H.pylori also causes duodenal and gastric ulcers. Infected persons have a 2- to 6-fold increased risk of developing gastric cancer and mucosal-associated-lymphoid-type (MALT) lymphoma compared with their uninfected counterparts. The role of H. pylori in non-ulcer dyspepsia remains unclear. Long-term consequences of H. pylori infection: Recent studies have shown an association between long-term infection with H. pylori and the development of gastric cancer. Gastric cancer is the second most common cancer worldwide; it is most common in countries such as Columbia How to prevent H. pylori infection : Since the source of H. pylori is not yet known, recommendations for Avoiding infection has not been made. In general, it is always wise for Persons to wash hands thoroughly, to eat food that has been properly Prepared, and to drink water from a safe, clean source. We now know that nine out of ten peptic ulcers are caused by an infection with the bacterium, Helicobacter pylori and not by stress or spicy foods as previously thought. Curing the infection with antibiotics shortens ulcer-healing time and significantly reduces the ulcer recurrence rate compared with traditional ulcer therapies such as acid-reduce in medications. H. Pylori infection can usually be cured with a two-week regimen of antibiotics. In more than 80 percent of patients, the ulcer is cured and does not recur. ___________________________________________________Section 6 Future Directions: Three new approaches to prevention and treatment of H. pylori are currently being studied: An oral vaccine composed of recombinant urease and Escherichia coli heat-labile toxin as a mucosal adjuvant, which has demonstrated both prophylactic and therapeutic qualities against Helicobacter felis in mice. A potential vaccine using recombinant heat-shock protein, another H. pylori antigen, which when fed to mice protected them against challenge with H. felis. An orally administered, naturally occurring carbohydrate that mimics epithelial bacterial adhesion ligands, thus inhibiting and reversing the adherence of H. pylori organisms to gastric epithelial cells, currently in a phase II clinical trial. The discovery of H. pylori as a gastrointestinal pathogen has had a profound effect on current concepts of peptic ulcer disease pathogenesis. Evidence presented led to the following conclusions: Ulcer patients with H. pylori infection require treatment with antimicrobial agents in addition to antisecretory drugs whether on first presentation with the illness or on recurrence. The value of treatment of nonulcer dyspepsia patients with H. pylori infection remains to be determined. The interesting relationship between H. pylori infection and gastric cancers requires further exploration. ___________________________________________________Section 7 Conclusion I conclude that a patient with PUD , should first undergo symptomatic treatment and then if , symptoms still persist then the underlying cause should be noted , by further investigations. Should also , state whether the ulcer is benign or malignant and avoid any of the aggressive factors which induces the peptic ulcer disease .If after and endoscopic investigation and outcome was that patient has Helicobacter pylori infection then a triple therapy would be an appropriate and effective treatment. Biography References: Basic Pathology 6th edition by Kumar ,Robbins and Cotran. Basic and Clincal Pharmacology by Katzung. BNF 39 March 2000 Handbook Gastroenterology (international diagnostic review) Drugs of Today , Prous science Drug facts and comparisons Clinical drug data