Antihypertensive Drugs Classification
These are drugs used to lower BP in hypertension. Hypertension is a very common disorder, particularly past middle age. It is not a disease in itself, but is an important risk factor for cardiovascular mortality and morbidity.
The cutoff manometric reading between normotensives and hypertensives is arbitrary. For practical purposes ‘hypertension’ could be that level of BP at or above which long-term antihypertensive treatment will reduce cardiovascular mortality. WHO have defined it to be 140 mm Hg systolic and 90 mm Hg diastolic, though risk appears to increase even above 120/80 mm Hg. Epidemiological studies have confirmed that higher the pressure (systolic or diastolic or both) greater is the risk of cardiovascular disease.
Majority of cases are of essential (primary) hypertension, i.e. the cause is not known. Sympathetic and renin-angiotensin systems (RAS) may or may not be overactive, but they do contribute to the tone of blood vessels and c.o. in hypertensives, as they do in normotensives. Many antihypertensive drugs interfere with these regulatory systems at one level or the other.
Antihypertensive drugs, by chronically lowering BP, may reset the barostat to function at a lower level of BP.
Thiazides: Hydrochlorothiazide, Chlorthalidone, Indapamide
High ceiling:Furosemide, etc.
K+ Sparing: Spironolactone, Amiloride
Captopril, Enalapril, Lisinopril, Perindopril, Ramipril, Fosinopril, etc.
Angiotensin (AT1 receptor) blockers
Losartan, Candesartan, Irbesartan, Valsartan, Telmisartan
Direct renin inhibitor
Calcium channel blockers
Verapamil, Diltiazem, Nifedipine, Felodipine, Amlodipine, Nitrendipine, Lacidipine, etc.
β Adrenergic blockers
Propranolol, Metoprolol, Atenolol, etc
β + α Adrenergic blockers
α Adrenergic blockers
Prazosin, Terazosin, Doxazosin, Phentolamine, Phenoxybenzamine
Arteriolar: Hydralazine, Minoxidil, Diazoxide
Arteriolar + venous: Sodium nitroprusside