Antihypertensive Drugs Classification | Antihypertensive Drugs List | Pharmacology Notes

Antihypertensive drugs

Anti-hypertensive are those drugs which are used to lower BP in hypertension.Hypertension is a very common disorder particularly in late middle age. It is not a disease by itself, but it is an important risk factor for cardiovascular mortality and morbidity.

Majority of cases are of essential (primary)
hypertension, i.e. the cause is not known. Sympathetic and renin-angiotensin systems may or may not be overactive, but they do contribute to the tone of blood vessels and c.o. in hypertensives, as
they do i normotensives. Many antihypertensive drugs interfere with these regulatory systems at one level or the other. Antihypertensive drugs, by chronically lowering BP, may reset the barostate to function at a lower level of BP.

classification of antihypertensive drugs

while classifying a drug in pharmacology it is essential to pre determine the basis on which the drug is being classified.
here with reference to antihypertensive drugs the basis of classification is their mode of action i.e its pharmacodynamics and their site of action.
a short, yet comprehensive classification of anti-hypertensive drugs is as follows.

• Sympatholytic drugs

sympatholytic or sympathoplagic are drugs that decrease sympathetic tone of the body thus decrease blood pressure in a manner.these drugs are further classified as.

1. centrally acting vasodilators  (methyl dopa,clonidine,guanabenz,guanadyl)

2. ganglion blockers (mecamyl amine,pempamine,hexamethonium,pentamethonium)

3. adrenoceptor antagonist (alpha blockers and beta blockers)

4. adrenargic neuron blockers(reserpine,guanadryl,bethanidine)

5. tyrosine hydroxylase inhibitors(methyrosine)

• Direct acting vasodilators

1. arteriolar dilators (hydralizine,minoxidil,diazoxide)

2. arteriolar plus venular dilators (sodium nitroprusside)

• rennin angiotensin aldosterone system(RAAS) system blockers

1. rennin release inhibitors (propranolol,clonidine,methyl dopa)
2. rennin action inhibitors (remikiren,aliskiren)
3. ace inhibitors (captopril,lisinopril,enalopril etc)
4. angiotensin ii receptor blockers (peptides i.e sarlasin and non peptides i.e sartan class)

• Calcium channels blockers

1. dihydrophyridine derivatives i.e dipine class (nifidipine,nimrodipine,amlodipine besylate,isradipine)

2. diphenyl alkylamine derivatives (verapamil,galopamil)

3. benzothizipine derivatives (diltiazem)

4. diaryl aminoprophyl ether (mibipradil,bipradil)

5. miscellaneous drugs (phenyl amine,lidoflazine)

• Diuretics

1. Diuretics targeting proximal convoluted part of nephron (carbonic anhydrase inhibitors,osmotic diuretics,acidifying salts,xanthine diuretics)

2. Diuretics targeting thick ascending loop of henle

   (high ceiling diuretics,mercural diuretics)

3. Diuretics targeting distal convoluted part of nephron

   (thiazide diuretics,sulphonamide diuretics)

4. Diuretics targeting collecting tubes of nephron 

   (potassium sparing diuretics,ADH antagonists)

5. Miscilinious Diuretics

   (citrate, acetate, bicarbonates of sodium and potassium)

also see  " Beta blockers classification and clinical uses "
alpha blockers classification