Antihypertensives_PPT.pptxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

ppt

1. Antihypertensive Drugs Classification, Mechanism, Uses, and Adverse Effects Your Name / Institution

2. Introduction • Hypertension = persistent rise in arterial blood pressure • Major risk factor for stroke, MI, heart failure, kidney disease • Goal: reduce morbidity & mortality by lowering BP

3. Classification of Antihypertensives 1. Diuretics 2. Sympatholytics (β-blockers, α-blockers, Centrally acting drugs) 3. Vasodilators 4. Calcium channel blockers 5. RAAS inhibitors (ACE inhibitors, ARBs, Renin inhibitors)

4. Diuretics Examples: Thiazides, Loop, K⁺ sparing Mechanism: Promote sodium and water excretion → ↓ blood volume → ↓ BP Uses: Mild–moderate hypertension Adverse effects: Hypokalemia, hyperuricemia, dehydration

5. β-blockers Examples: Propranolol, Atenolol, Metoprolol Mechanism: Block β1-receptors → ↓ HR & contractility, ↓ renin release Uses: Hypertension with angina, post-MI, arrhythmias Adverse effects: Bradycardia, fatigue, bronchospasm

6. α-blockers Examples: Prazosin, Terazosin Mechanism: Block α1-receptors → vasodilation → ↓ TPR Uses: Resistant hypertension, BPH Adverse effects: Postural hypotension, dizziness

7. Centrally Acting Drugs Examples: Clonidine, Methyldopa Mechanism: Stimulate central α2 receptors → ↓ sympathetic outflow Uses: Methyldopa in pregnancy hypertension Adverse effects: Sedation, rebound hypertension (clonidine)

8. Vasodilators Examples: Hydralazine, Minoxidil Mechanism: Direct relaxation of vascular smooth muscle → ↓ TPR Uses: Severe / resistant hypertension Adverse effects: Reflex tachycardia, fluid retention, hypertrichosis (minoxidil)

9. Calcium Channel Blockers (CCBs) Examples: Amlodipine, Nifedipine, Verapamil, Diltiazem Mechanism: Block Ca²⁺ entry → vasodilation, ↓ HR (non-DHP) Uses: Hypertension, angina, arrhythmias Adverse effects: Ankle edema, constipation, bradycardia (non-DHP)

10. RAAS Inhibitors ACE Inhibitors (Enalapril, Lisinopril) – block Ang I → Ang II ARBs (Losartan, Valsartan) – block Ang II AT1 receptors Renin Inhibitor (Aliskiren) – blocks renin activity Uses: Hypertension, CHF, diabetic nephropathy Adverse effects: Cough (ACEi), hyperkalemia, angioedema

11. Combination Therapy Used in resistant hypertension Examples: • Diuretic + ACE inhibitor • β-blocker + vasodilator • CCB + ARB

12. Special Considerations Pregnancy: Methyldopa, labetalol, nifedipine safe Diabetes: ACE inhibitors/ARBs preferred Asthma: Avoid non-selective β-blockers

13. Summary • Hypertension → major CV risk factor • Multiple drug classes with different mechanisms • Choice depends on patient comorbidities • Monitoring of side effects is essential

14. References Goodman & Gilman’s Pharmacology Katzung’s Basic & Clinical Pharmacology Standard treatment guidelines