* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Drugs used to treat Hypertension
Survey
Document related concepts
Pharmacokinetics wikipedia , lookup
Discovery and development of integrase inhibitors wikipedia , lookup
Toxicodynamics wikipedia , lookup
Pharmacogenomics wikipedia , lookup
Pharmaceutical industry wikipedia , lookup
Prescription costs wikipedia , lookup
Pharmacognosy wikipedia , lookup
Discovery and development of beta-blockers wikipedia , lookup
Discovery and development of angiotensin receptor blockers wikipedia , lookup
Norepinephrine wikipedia , lookup
Drug interaction wikipedia , lookup
Discovery and development of ACE inhibitors wikipedia , lookup
Neuropharmacology wikipedia , lookup
Transcript
Drugs used to treat Hypertension HTN = BP > 140/90 Assos. With: premature death vascular disease of brain, heart,kidneys Goal of treatment Prolong useful life by preventing cardiovascular problems by reducing BP < 140/90 Blood Pressure Review of physiology BP caused by: _________ Systolic pressure: __________ Diastolic pressure: __________ Blood Pressure 1. 2. 3. Primary Factors Cardiac output Peripheral resistance Blood Volume Initial tx. of hypertension Lifestyle modification first No smoking Weight control Reduce alcohol intake Decrease stress Sodium control Treatment of hypertension Lifestyle modification first Initial tx. drug- diuretic or B-blocker Low dose first, increase dose if necessary 2nd med. if needed Most respond with diuretic and one other medication (stepped care) Tx pump, fluid volume, or PVR Drugs to treat hypertension 1. 2. 3. 4. 5. 5 primary classes Diuretics Calcium channel blockers Angiotesin converting enzyme (ACE) inhibitors Autonomic nervous system agents Direct acting vasodilators Diuretics Tx: mild to moderate HTN First drug of tx. Also tx. heart failure or kidney disease Few adverse side effects Used with other antihypertensives to enhance effectiveness Diuretics Action 1. 2. Reduce blood volume through urinary excretion of water and electrolytes Electrolyte imbalances can occur (mainly hypokalemia) Depends on type of diuretic Diuretics Most efficient: Loop or High-ceiling Reduce edema assos. with CHF Increase UO even if blood flow to kidney is diminished Hypokalemia KCL supplement given Lasix, Demadex, Bumex Diuretics Most widely prescribed: Thiazides Mild to moderate HTN-primarily Hydrodiuril – hydrochlorothiazide (HCTZ) Hypokalemia Potassium supplement- KCL Diuretics Potassium-sparing:prevent hypokalemia Mild HTN Used in combination with other diuretics No supplement taken Watch for hyperkalemia Side effects Orthostatic hypotension Dry mouth,irritation Report: Electrolyte imbalance- hypokalemia (potasium<3.5) Disorientation dehydration Implications for use Optimal time to admin.= AM Check VS Accurate intake and output Daily weights Monitor electrolyte imbalances Calcium Channel Blockers Emerged as major drug to tx. HTN Used for arrythmias also Alternative to B-blocker (hx. Asthma) Calcium Channel Blockers Action: blocks ca+ access to muscle cells contractility + conductivity of the ______________________ demand for oxygen PVR (relaxing arterioles) Calcium Channel Blockers Examples Verapamil Very Procardia (nifedipine)-HTN Cardizem (diltiazem)-arrythmias Drugs Nice Calcium Channel Blockers SIDE EFFECTS BP Bradycardia May precipitate A-V block Headache Abdominal discomfort Peripheral edema Angiotensin-Converting Enzyme Inhibitors “ACE” inhibitors Mainstay of oral vasodilator therapy Major breakthrough in tx. of HTN More effective when used with diuretics ACE INHIBITORS Angiotensin Converting Enzyme (ends in PRIL) captopril (Capoten) enalapril (Vasotec) benzapril (Lotensin) RENIN-ANGIOTENSINALDOSTERONE AXN. BP excrete renin formation of angiotensin I angiotensin II = potent vasodilator Aldosterone release Na and H2O ACE INHIBITORS ACTION peripheral vascular resistanse without Ø Ø Ø cardiac output cardiac rate cardiac contractility Advantages Infrequent orthostatic hypotension Lack of aggravation of pulmonary dx. Lack of aggravation with DM Increase renal blood flow Side effects Headache Orthostatic hypotension-infrequent Cough GI distress Drug interactions Diuretics Alcohol Beta-blockers All the above enhance the effects Adrenergic Receptors Review of ANS Sympathetic Nervous System Alpha 1 = vasoconstriction Alpha 2 = feedback/vasodilation Beta 1 = increases heart rate Beta 2 = bronchodilation Beta Adrenergic Blocking Agents Known as Beta-blockers Axn: Inhibit cardiac response to sympathetic nerve stimulation by blocking Beta receptors Decreases heart rate and C.O. Decreases blood pressure Beta Adrenergic Blocking Agents Examples – “olol” names Beta 1: Atenolol Beta 1 and 2: Propranolol Nursing Implications Can not be abruptly discontinued Check baseline b.p. Check hx. of resp. condition-aggravates bronchoconstriction Side effects Bradycardia Bronchospasm, wheezing Diabetic: hypoglycemia Heart failure: edema,dyspnea,rhales Interactions Antihypertensives- additive effect B-adrenergic agents- inhibit axn. Enzyme inducing agents-enhance metabolism Indomethacin and salicylates:< controll Alpha-1 adrenergic blockers Alternative if B-blockers and diuretics do not work Also used to tx. mild to mod. urinary obstructive dx. (BPH) Alpha-1 Adrenergic Blocking Agents Action: Block postsynaptic alpha-1 adrenergic receptors to produce arteriolar and venous vasodilation Reduces peripheral-vascular resistance Side effects Drowsiness Headache Dizziness,tachycardia,fainting Weakness,lethargy Interactions: other antihypertensives (enhance effects) Clinical Implications Side effects most prevalent with first dose Warn pt. that this is nl. Instruct pt. to lie down if dizzy,weak,etc. Examples of Apha-1 blockers Cardura (doxizosin) Minipress (prazosin) Hytrin (terazosin) Centrally Acting Alpha-2 Agonists Stimulate Alpha-2 receptors in brainstem Decreases HR, SBP and DBP More frequent side effects – drowsiness, dry mouth, dizziness Never suddenly DC = rebound HTN Clonidine – Catapres ( available in TTS) Methyldopa - Aldomet Direct Acting Vasodilators Action: dirct arteriolar smooth muscle relaxation, decreasing PVR Uses: HTN, renal dx., toxemia of pregnancy Ex: Apresoline, Minoxidel SE: tachycardia, orthostatic hypotension,dizziness, palpitations, nausea, nasal congestion Client Teaching for Antihypertensive drugs Take medication as prescribed Never discontinue without approval of healthcare provider Incorporate lifestyle changes, even if medication brings BP within nl. Limits Check BP on regular basis and report significant variations (and pulse) Get out of bed slowly Client Teaching for Antihypertensive drugs Increase intake of potassium-rich foods, unless taking potassium sparing diuretics Weigh regularly and report abnormal weight gains or losses Do not take OTC drugs without checking with healthcare provider