antihypertensives drugs

PRESENTED BY:-

Dr Nikhil

Bansal

J.N.M.C.,Wardha

CLASSIFICATION OF ANTIHYPERTENSIVES DRUGS

The drugs used in the treatment of hypertension act by reducing the cardiac output and/or reducing the total peripheral resistance, without correcting the cause.

CLASSIFICATION:-1)Drugs acting centrally.2)Drugs acting on autonomic ganglia.3)Drugs acting on the postganglionic sympathetic nerve

ending.4)Drugs acting on the adrenergic receptors.5)Drugs acting on the vascular smooth muscle.6)Potassium channel activators.7)Drugs which block renin-angiotensin-aldosterone axis.8)Oral diuretics.9)Miscellaneous.

Drugs acting centrally:-

(a)Alpha2 adrenergic receptor stimulants:- eg:- Clonidine and methyldopa

(b) Selective imidazole receptor (I-receptor) Stimulant:- eg:- Moxonidine

Drugs acting on the autonomic ganglion:-

Ganglion blocking agents eg:- Trimethaphan

Drugs acting on the postganglionic sympathetic nerve endings:-

(a) Adrenergic neuron blockers eg:- Guaenethidine, Bethanidine, Debrisoquine,

Bretylium.

(b) Catecholamine depletors eg:- Reserpine

Drugs acting on adrenergic receptors :-

(a) Alpha-adrenergic blocking agents eg:- Phentolamine, Phenoxybenzamine, Prazosine,

Indoramine. (b) Beta-adrenergic blocking agents eg:- Propranol, Atenolol, Metopprolol. (c) Both alpha and beta adrenergic blocking drugs eg:- Labetalol

Drugs acting directly on the vascular smooth muscle:-

(a)Arteriolar vasodilators eg:- Calcium channel blockers, Hydralazine,

Diazoxide, Minoxidil (b) Arteriolar-venular vasodilators

eg:-Sodium nitroprusside

.

Potassium channel activators:- eg:-Diazoxide, Minoxidil, Pinacidil, Nicorandil.

Drugs which block renin-angiotensin-aldosterone axis:-

(a)Those which block renin release eg:- Beta-adrenergic blockers

(b) Those which block the conversion of angiotensin I to angiotensin II:-

These drugs act by inhibiting the angiotensin converting enzyme (ACE) eg:- Captopril, Enalapril(c) Those which competitively block angiotensin II vascular receptors (ARB): eg;- Losartan.(d) Those which counterer the action of aldosterone (Aldosterone antagonist):- eg:- Spironolactone.

Oral diuretics:- eg:-Thiazides

Miscellaneous:- eg:- Metyrosine

It must be emphasized that various antihypertensive

drugs may ultimately reduce BP in humans by more than one mechanism.

THANK YOU