Pharmacology Lec8: Anti-Hypertensive Drugs - PDF

Pharmacology Course Lec8 For Level 1 Nursing Students 2024-2025 By Ass. Prof. Marwa E. Abdelmageed Pharmacology and Toxicology Department Faculty of Pharmacy, Mansoura University 1 12. Therapy of Hypertens...

Pharmacology Course Lec8 For Level 1 Nursing Students 2024-2025 By Ass. Prof. Marwa E. Abdelmageed Pharmacology and Toxicology Department Faculty of Pharmacy, Mansoura University 1 12. Therapy of Hypertension 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 2  A) Non-pharmacological Approaches  Salt intake  Body weight Cessation of smoking Cessation of alcohol Regular physical activity Stress avoidance (both drinking and relaxation physical & mental) Coffee restriction N.B. Avoids agents that increase blood pressure (BP) as sympathomimetics, steroids, NSAIDs, oral contraceptives, and products that contain large quantities of sodium e.g. effervescent 4/11/2025 solutions. Pharmacology for Nursing Dr. Marwa E. Abdelmageed 3  Examples of antihypertensive drugs: 1. Kidney I. Thiazide → ex: Hydrochlorothiazide Hypokalemia –Hypomagnesemia –Hypercalcemia –Hyperglycemia Side –Hyperuricemia -Postural Effects hypotension (rare) The incidence of S/E reduced with low dose of diuretics Patients having renal stones & C/I patients with poor renal function (poor glomerular filtration rate) Postural hypotension (an exaggerated decrease in blood pressure upon standing, often associated with syncope) 4/11/2025 4 II. Thiazide like diuretics Indapamide ✓ Lipid soluble ➔ Duration of action (DOA) ( frequency of urination) ➔ used with elderly. ✓ Metabolized and excreted by GIT & kidney ➔ less like to accumulated in patients with renal failure ➔Useful in their treatment 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 5 III. Loop diuretics (high ceiling diuretics- Produce peak diuretic) ex : Furosemide, Bumetanide, Torsemide ➔ S/E Ototoxicity 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 6 IV. K+ sparing diuretics (overcome K+ loss) Prevents excessive excretion of K+ in urine and decreased retention of water, preventing hypokalemia Spironolactone - Amiloride mild edematous Hyperkalemia, state for few days peptic ulcers Use S/E 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 7  2- Sympatholytic Remember Lec 3 -Adrenergic Therapeutic Uses of - blockers in HTN Receptor Cardio selective β- blockers (β1- blockers) are preferred in Antagonists asthmatics & diabetics (Atenolol & Metoprolol) Centrally Acting -Methyldopa (Aldomet)→Methyldopa is often preferred for Drugs the treatment of hypertension in pregnant women, since long (methyldopa): experience has shown that it does not harm the fetus. 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 8 3- Angiotensin-converting-enzyme inhibitors (ACE inhibitors) Captopril, Enalapril, Lisinopril, Ramipril, …… Pril Side effects ► fetal and neonatal morbidity and mortality when administered to pregnant women, especially during the second and third trimesters. ► The most common is a dry, irritating and nonproductive cough, which occurs in up to 20% of patients and may be due to increased bradykinin levels. ► Rash occurs in up to 10 % of patients. Angiotensin receptor antagonists (Losartan, Valsartan) In the treatment of hypertension, these drugs appear to be as effective as the ACE inhibitors but only rarely cause the chronic cough. 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 9 4-VASODILATORS Calcium channel blockers (CCBs) Class 1 (Vasodilation): Nifedipine, Amlodipine, Examples nicardipine, felodipine Class 2 (Heart): Verapamil, diltiazem Used in Hypertension, Angina, Arrythmia 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 10  1) HTN emergency: HTN crisis with end organ damage Parenteral therapy in ICU with rapid lowering of BP: Na nitroprusside (I.V. inf)., Nitroglycerine (I.V. inf), Loop diuretic as Furosemide (Lasix, I.V.), Labetalol (I.V. bolus), Enalapril (I.V). Avoid excessive fall of BP to avoid hypoperfusion of vital organs that may results in stroke & MI. A hypertensive emergency is an acute, marked elevation in blood pressure that is associated with signs of target-organ damage. These can include pulmonary edema, cardiac ischemia, neurologic deficits, 4/11/2025 11 acute renal failure, aortic dissection, and eclampsia.  2) HTN urgency: HTN crisis without end organ damage Need prompt medical attention BUT lowering BP can be achieved within 24-48 h. Use vigorous oral therapy in outpatient clinic. e.g., Captopril can be used for treatment of HTN urgency. 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 12 11. Angina pectoris - Angina pectoris is the principal symptom of ischemic heart disease -  O2 supply by coronary arteries (partial obstruction) caused by: ➔Atherosclerosis ➔Coronary vasospasm -  in oxygen demand by the heart Hypertension Overloads on the heart Tachycardia Anxiety Stable angina Unstable angina Vasospastic 4/11/2025 13 angina  Principles of Antianginal Therapy Increase oxygen supply Reduce oxygen demand Approaches used in the treatment of angina pectoris A) Non-drug therapy: → Avoiding smoking → Avoiding fatty diet → Avoiding stress and/ or emotion → Weight reduction B) Surgical treatment (in severe cases or MI) 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 14 C) Drugs or Pharmacotherapy 1. Organic nitrates: Nitroglycerin, Na nitroprusside 2. -adrenergic blockers: Propranolol (Inderal), Atenolol (Tenormin). 3. Ca++ channel blockers: Nifedipine 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 15 Therapeutic uses of Organic nitrates A. Angina Pectoris: Treatment of all types of anginas (exertional, vasospastic and unstable angina) B. Heart Failure C. Hypertensive Emergency: I.V. Nitro-glycerine Contraindications of organic nitrates phosphodiesterase-5 inhibitors (sildenafil) as it lead to marked Hypotension. 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 16 Precautions  Start with the smallest possible dose to minimize side effects.  Nitrate therapy should not abruptly stop to avoid withdrawal symptoms.  The patient should consult his doctor when more than 3 tablets sublingually taken over 15 minutes without improvement for fear of MI.  The expiry date should be checked (active tablets have burning taste). -adrenergic blockers: Effective against exertional angina (stable). 4/11/2025 Pharmacology for Nursing Dr. Marwa E. Abdelmageed 17 End of Lecture Thank You