Antianginal drugs Classification | Mechanism Of Action | Pdf Ppt Download

introduction To Antianginal drugs

Antianginal drugs can be simply defined as "The drugs used for therapeutically treating angina pectoris and myocardial infarction."

both of them are ischemic heart diseases with minor difference.

the cause of ischemic heart disease is as the name indicates ischemia i,e a decreased oxygen supply to myocardial tissues.heart muscles would work ideally when there is a balance between oxygen supply and oxygen demand.if oxygen demand increases like in case of stressful exercise, An imbalance can occur.on the other hand decreased oxygen supply may be due to the atheloschlerosis of coronary artery (athelosclerotic angina) or by angiospasticity of coronory artery (angiospastic angina) both of which causes decrease blood flow to heart muscles and so a lesser oxygen supply.

keeping this basic pathophysiology of angina the drugs used should alter mechanism at any step so that either the supply of oxygen increases or the demand decreases or both occur.

Mechanism Of Action Of Antianginal Drugs:

The mechanism of action can vary depending upon the pharmacological class of the drugs used.the the mechanism can be classified simply into major divisions.

• Drugs lowering cardiac load
• Drugs increasing oxygen supply

some drugs can show their Mechanism of action by playing part in both of these aspects, like coronary vasodilators that increases oxygen demand by vasodilation, Also decrease demand by lowering preload. Other drugs are beta blockers that simply act as sympatholytics. antihyperlipidemics like HMGco-A reductases decrease lipid profile and can prevent successive attacks. Antiplatelet aggregation drugs like aspirin can also help this way by minimizing athelosclerosis.

Classification Of Antianginal Drugs:

These drugs can be classified into following classes.

• Coronary vasodilators
• Beta blockers
• Calcium channel blockers
• Antiplatelet aggregation

1) Coronary vasodilators

in coronory vasodilators there is further classification into

1. nitrates
2. nitrites

the nitrites can be inorganic like sodium nitrite, or organic i,e amyl nitrate and ethyl nitrate.

the nitrates are all organic coronory vasodilators having the following examples.

• glyceryl trinitrate
• iso-sorbide dinitrate
• iso-sorbide mononitrate
• erythryl tetranitrate
• penta erythretol tetra nitrate

2) Beta blockers

Not all beta blockers are clinically used as antianginal.following are the beta blockers of clinical importance as antianginal.

• metoprolol
• atenolol
• nadolol
• oxprenolol
• propranolol

3) Calcium channel blockers

calcium channel blockers are

• nifidipine
• amlodipine
• verapamil
• diltiazem

4) Anti-platelet aggregators

this class include the following drugs

• low dose aspirin
• clopidrogel
• triclopidine

download As antianginal drugs classification pdf