Reviewed by Dr. A M Thirugnanam, MD, MSICP, FSCAI, Ph.D. — Senior Interventional Cardiologist
Patients are handed a strip of tablets and told to take them. Very few are told what each one does, and almost none are told what happens if they stop. Understanding your medicines is the difference between taking them for life and quietly abandoning them within a year — which is what a large proportion of Indian cardiac patients do.
This guide explains the main classes. It is not a substitute for your own prescription, and nothing here should prompt you to change a dose on your own.
Aspirin and other antiplatelets
What they do: make platelets less sticky, so a clot is less likely to form on a ruptured plaque or a stent.
Common names: aspirin, clopidogrel, ticagrelor, prasugrel.
Key point: after a stent, most people take two of these together for a defined period — usually six to twelve months. Stopping early can cause the stent to clot, which is often fatal. If any doctor or dentist asks you to stop before a procedure, that must be cleared with your cardiologist first.
Side effects: bruising, and bleeding from the stomach. Report black stools or vomiting that looks like coffee grounds urgently. A stomach-protecting medicine is often prescribed alongside.
Important: aspirin for primary prevention — in someone who has never had an event — is no longer routinely recommended, because the bleeding risk often outweighs the benefit. If you started aspirin yourself without a cardiac diagnosis, ask whether you still need it.
Statins
What they do: lower LDL cholesterol and stabilise existing plaque so it is less likely to rupture. Their benefit extends beyond the cholesterol number itself.
Common names: atorvastatin, rosuvastatin, simvastatin.
Key point: cholesterol produces no symptoms, so there is nothing to feel better from — which is precisely why people stop. Stopping returns risk to baseline within weeks.
Side effects: muscle aches in a minority. In blinded trials, most people who report muscle aches on a statin report them equally on placebo, which does not make the symptom imaginary but does mean a different statin or dose usually solves it. Do not simply stop — ask for an alternative.
Ezetimibe is often added rather than pushing the statin to maximum dose. Grapefruit interacts with some statins; this is rarely relevant in India.
Beta blockers
What they do: slow the heart, reduce its workload and oxygen demand, and reduce the risk of dangerous rhythms. Prognostically important after a heart attack and in heart failure.
Common names: metoprolol, bisoprolol, carvedilol, nebivolol.
Key point: never stop abruptly. Sudden withdrawal can cause a rebound surge in heart rate and blood pressure, and can precipitate angina.
Side effects: tiredness, cold hands and feet, vivid dreams, reduced exercise capacity, sometimes erectile difficulty. A resting pulse in the fifties is usually intended, not a problem. Report a pulse persistently below fifty with dizziness.
ACE inhibitors and ARBs
What they do: relax arteries, lower blood pressure, protect the kidneys, and prevent the heart from remodelling into a weaker dilated shape after damage.
Common names: ramipril, enalapril, lisinopril (the -prils); telmisartan, losartan, olmesartan (the -sartans).
Key point: a persistent dry cough affects a noticeable minority on the -pril group. It is not an allergy and it is easily solved by switching to a -sartan. Many patients suffer it silently for years.
Monitoring: kidney function and potassium should be checked after starting and after any dose increase. These drugs must be stopped in pregnancy.
Calcium channel blockers
What they do: relax arteries, lowering blood pressure and relieving angina.
Common names: amlodipine, cilnidipine, diltiazem, verapamil.
Side effects: ankle swelling with amlodipine is common and dose-related. It is not fluid retention from heart failure and does not respond to diuretics — the answer is a dose change or a switch.
Diuretics
What they do: remove excess fluid, relieving breathlessness and swelling in heart failure; also used for blood pressure.
Common names: furosemide, torsemide, chlorthalidone, spironolactone.
Key point: take them in the morning unless told otherwise, or you will be awake all night. In heart failure, weigh yourself daily at the same time — a gain of two kilograms or more over a few days signals fluid retention and needs medical advice.
Monitoring: sodium, potassium and kidney function need periodic checking.
Anticoagulants
What they do: prevent clot formation in atrial fibrillation, after certain valve surgery, or after a clot in the leg or lung. These are stronger than antiplatelets and are not interchangeable with aspirin.
Common names: warfarin, acenocoumarol; and the newer agents apixaban, rivaroxaban, dabigatran.
Key point: warfarin needs regular INR blood tests and interacts with many foods and drugs. The newer agents do not need routine monitoring but must be taken with strict regularity — missing doses removes protection quickly.
Report urgently: any unusual bleeding, black stools, blood in urine, or a significant head injury.
How to take them well
- Use a weekly pill organiser. It works better than memory or discipline.
- Keep one updated list of every medicine, including doses, on your phone and in your wallet.
- Ask whether a combination tablet could reduce the number you take.
- Tell every doctor — including dentists and eye surgeons — that you are on blood thinners.
- Do not take painkillers such as diclofenac or ibuprofen regularly without asking; they raise blood pressure and cardiovascular risk. Paracetamol is generally safer.
- Be cautious with ayurvedic and herbal preparations alongside anticoagulants. Interactions are real and under-reported. Tell your cardiologist what else you take.
- Order the next month’s supply a week early. Most missed doses are supply failures, not forgetfulness.
What to ask your doctor
- What does each of these tablets do, and which are the ones I must never stop?
- How long am I expected to stay on each?
- Which blood tests do I need, and how often?
- Can any of these be combined into fewer tablets?
- Which side effects should make me call you rather than simply stopping?
Emergency: call 108 or go to the nearest hospital. Do not use this website.
This guide is educational and does not replace your own prescription or your doctor’s advice. Never start, stop or change a cardiac medication on the basis of anything you read here.
Take the free 3-minute heart risk check · See membership plans · Back to the education library