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Week – 4
 Drugs
Pharmacology
and Disorders of the
Gastrointestinal Tract
Nutritional
Supplements
chapters – 20 and 25
VITAMINS, MINERALS, AND
GENERAL NUTRITION
CHAPTER - 20
“YOU ARE WHAT
YOU EAT”
Your body needs a balance of
nutrients for optimum health …
Water
Minerals/Vitamins
Proteins/Carbohydrates
Fiber
Essential fatty acids
FOOD & NUTRITION BOARD OF
THE NATIONAL ACADEMY OF
SCIENCE
o a DRI is a ‘Dietary Reference Intake’ for
vitamins and minerals:
EAR (Estimated Average Requirement)
RDA (Recommended Daily Allowance)
AI (Adequate Intake)
UL (Upper Intake Level)
o VitaminsOrganic materials required in minute amounts/ we can’t
manufacture.
o Minerals- non-organic material, found in the “earth”.
o Essential fatty acids- found in fats, not produced by the body
made up of carbon and hydrogen.
o Antioxidants - inhibit oxidation, reducing tissue damage/aging:
 Vitamin C
 Vitamin E
 Lutien
o Fiber A food substance, found only in plants… not digested “roughage”
VITAMINS
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CHARACTERISTICS
Organic in nature
Very small amounts needed daily
Ingested in the diet or synthesized by intestine
NECESSARY for body’s normal growth & function
Store in dark containers in a cool place
NECESSARY for enzymatic reactions
Can be taken in excess
Common vitamin-deficiency symptoms include
- aches/pains
- general, overall ‘poor’ feeling
- tiredness/low energy
See 384
‘FAT SOLUBLE’ VITAMINS
What do you know about these?
Vitamin A
Vitamin D
Vitamin E
Vitamin K
THESE CAN ACCUMULATE…WATCH
FOR SIGNS OF EXCESS!
‘WATER SOLUBLE’ VITAMINS
Vitamin B’s
1)
Those that release energy from food
Thiamine, Riboflavin, Niacin, Biotin
2)
Those that aide in red blood cell formation
Folic acid, Cyanocobalamin
Vitamin C
AKA _______________
Wound healing, resistance to infections
FOLIC ACID IN PREGNANCY
o Extremely important supplement for
women!
o Reduces the incidence of neural tube birth
defects such as …
* Spina Bifida
* anenchephaly
* encephalocele
o … essential for DNA formation
o Women of childbearing age should consume
0.4-mg/day of Folic acid
o Also known as ‘Folate’
MINERALS
o Iron – (oral, injectable)
o Calcium (lactate/glucomate/chloride/
carbonate)
o Phosphorous
o Potassium –
(chloride/gluconate)
oFreely found in soil, plants
used for food, and sea food.
oOnly required in trace
amounts
oRole in transmission of nerve
impulses
oControl of cardiac rhythm
oExist as acids, bases, salts (aka
electrolytes)
QUESTIONS!
1) The disease that develops due to a
vitamin overdose is…?
2) A non-organic material found in the
Earth’s crust is a…?
ANSWERS!
1) Hypervitaminosis
2) Mineral
Healthy Dinner?
The Gastrointestinal System
Chapter 25
GI TRACT – A DEFINITION
Long, hollow tube from the mouth to the
anus
 Primary purpose - to convert food into
chemicals that can be used by the body
 Food’s pathway through GI tract …
… Mouth  Esophagus  Stomach Small
Intestines  [gallbladder, liver, pancreas
enzymes]Large Intestine Anus
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HOW DRUGS WORK IN THE GI
SYSTEM

1. They increase or decrease function by
changing muscle tone, or changing the
level of secretions (for example …
decreasing the level of acid-production to
prevent or cure ulcers)
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2. Increase or decrease ‘emptying time’
(the time it takes food to pass through the
stomach/GI tract) … this is accomplished by
altering ‘peristalsis’
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3. Replacement of enzymes (in cases of
deficiency)
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LIFESTYLE MODIFICATIONS for
GI PROBLEMS
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Foods to avoid
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Don’t over eat, maintain ‘normal’ weight
Avoid eating within 2 hours of bedtime
Don’t smoke
Elevate head of the bed 6-8 inches (gravity
can help empty the stomach!)
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Tomato
Orange/Grapefruit juice
ETOH
Caffeine
Chocolate
Peppermint
GASTRIC
CONDITIONS/ENVIRONMENT
Acidic environment is needed in the stomach for
enzymes to work and inhibit or kill microorganisms
found in food and other materials that are ingested
 Sometimes acid level is too high and can erode the
stomach wall/lining
 Worry and Stress increase secretions in the stomach
 This can lead to ulcers

◦ Gastric ulcer = Peptic ulcer = stomach ulcer (all the same)
◦ ‘Duodenal ulcer’ is found at the junction of stomach and
duodenum
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ULCERS – GENERAL INFO
Cause of ulcers:
◦ ___________________bacteria has been found
in >75% of peptic ulcer disease!
◦ Remaining 25% caused by NSAID & ASA use
Opportunistic infection at the site
of the ulcer.
Goal of treatment:
◦ to alleviate symptoms, promote healing, prevent
complications, and prevent recurrence.
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ULCERS (CONT.)
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Eating multiple small meals decreases
changing acid levels
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Drugs (ASA and NSAID’s) can cause
irritation to the stomach
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Smoking slows the healing of ulcers …
it increases acid production
MEDICATIONS TO TREAT
ULCER

All these work together to eradicate the
microorganism Helicobacter pylori and
reestablish an intact lining of the stomach
by neutralizing excess hydrochloric acid.
◦ Antacids (neutralizes acid that is currently present)
◦ Mucosal protectants (forms a protective barrier on
the surface of ulcerated tissue)
◦ Antibiotics
◦ Antisecretory Agents (reduce excess acidproduction)
◦ Antispasmodics
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ANTACIDS
Alkaline compounds used to neutralize
HCl acid in the stomach
 Used as prophylaxis for stress-induced
ulcers
 Relieves symptoms of Gastroesophageal
Reflux Disease (GERD)
 Protect intestinal mucosa by neutralizing
acid
 Poorly absorbed (this is good!), therefore
they do not alter systemic pH when used
properly
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ANTACIDS
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CONTINUED
More effective when taken on a regular basis
Can be dosed up to 7 times per day (before meals,
after meals, and bedtime)
Come in liquids, chew tabs, and a few swallow
tabs or caps.
 Short duration of action … ~ 30 minutes on
empty stomach
 Chronic use can produce acid rebound
 Classified by formulation (aluminum, magnesium,
etc)
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ANTACID FORMULATIONS
Aluminum (side-effect = Constipation)
Calcium (side-effect = Constipation)
Magnesium (side-effect = Diarrhea)
Sodium (can change systemic pH – dangerous
choice)
 Aluminum & Magnesium combo is common
because these cancel out each other’s negative
side-effects … very effective!
 Choose product with care, based on patient’s profile
 NOTE - sodium bicarbonate changes the pH
(acid/base balance) in the body and can lead to
other problems
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PATIENT EDUCATION FOR
ANTACIDS
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Chewable antacids should be taken with a full
glass of water or milk to help with absorption
Shake liquids well and don’t follow with
additional liquids … this dilutes the antacid,
reducing its effect
Antacids and H-2 blockers should be taken at
least an hour apart, antacids first.
Careful when taking other medications, these can
interfere with absorption of other drugs
Examples of Antacids …
◦ Mylanta, Maalox
◦ Tums, Rolaids
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ANTISECRETORY AGENTS
These DECREASE THE SECRETION of gastric fluids
(acid)
 Two types
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◦ H2-receptor antagonists (H2)
 Zantac (ranitidine)
 Pepcid (famotidine)
◦ Proton pump inhibitors (PPIs)
 Prilosec (omeprazole)
 Previcid (lansoprazole)
 Nexium (esomeprazole)
* NOTE – see how the generic drug names within the same class
tend to end with the same suffix? This is very helpful in learning
drugs!
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H2-RECEPTOR ANTAGONISTS
Inhibits interaction of histamine (H2) at the
H2-receptors
 Histamine receptors in gastric mucosa
mediate the secretion of gastric acid and
pepsin
 Work to directly inhibit the acid secretions
 Not affected by food (ok with or w/o meals)
 best to take at bedtime (acid production
peaks during the overnight hours!)
 Well tolerated, low incidence of side-effects
 Very effective for GERD
 Available as OTC and RX
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PROTON PUMP INHIBITOR (PPI)
Inhibits chemicals essential to Gastric-acid
production (H+ and K+ ions, which
generate gastric acid)
 For SHORT TERM treatment of benign
gastric ulcers and GERD!
 often used in combo with antibiotics for H.
pylori to promote healing and prevent
reoccurrence
 Should only be used for confirmed
active ulcers and erosive esophagitis.
 Side effects are relatively rare (headache,
abdominal pain, diarrhea, nausea,
constipation are possible)
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PROTECTANTS
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Carafate (sucralfate)
◦ Adheres to ulcerated tissue, forming a barrier
◦ Soothing effect like Antacids
◦ Does not alter pH
◦ Take on empty stomach
Cytotec (misoprostol)
◦ Protects from irritation of certain medications,
like NSAIDS
◦ Used to prevent ulcers in patients who must take
medications that can cause gastric irritation
◦ Take on a empty stomach
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ANTIBIOTICS
Commonly used to treat Heliobacter pylori
 Treatment with two antibiotics decreases
resistance
 Used in combo with bismuth-salts to prevent
bacteria from attaching stomach wall.
 Antibiotics that are commonly used …
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Amoxicillin
Tetracycline
Metronidazole (Flagyl)
Clarithromycin (Biaxin)
Antisecretory agents often used in combo
(PrevPak)
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See table 25-6 in text on page 503
ANTISPASMOTICS
These relax GI smooth-muscle tissue, reducing
cramping and spasms (IBS)
 Not as commonly used as the previously
mentioned medications due to more frequent
Side-Effects
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◦ Cause problems in glaucoma & urinary
retention patients
More Side Effects …
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Visual disturbances
Confusion in demented patients
Changes in heart rhythm
Headache
Insomnia
HAVE A GREAT WEEK, THANKS
FOR YOUR INPUT!
Remember, you are welcome to submit any
and all questions to me as they arise … I
check my email daily,