Written & medically reviewed by Dr. Sanjay Anbu, MBBS· Last reviewed
Warfarin is a long-established blood thinner needing regular INR monitoring. It belongs to the Blood thinner (anticoagulant) group. These reduce the blood’s tendency to clot, preventing strokes and dangerous clots.
Treating and preventing deep-vein clots and lung clots
After certain heart valve or clot conditions
Common brand names
India: Warf, Uniwarfin
Worldwide: Coumadin, Jantoven
Common side effects
Easier bruising or bleeding
Nosebleeds or gum bleeding
Heavier periods
Before taking it — precautions
Tell every doctor/dentist you take a blood thinner
Warfarin needs regular blood (INR) tests and diet consistency
Avoid unnecessary NSAIDs (bleeding risk)
When to see a doctor urgently
Black stools, blood in urine/vomit, or coughing blood
A severe headache or a bad fall (internal bleeding)
Bleeding that will not stop
Not a prescription — no dose shown. The right dose of warfarin depends on age, weight, kidney/liver function and the condition, so MedDroid does not show a dose here. Always get your dose from a doctor or pharmacist and the leaflet inside the pack. General educational information only.
Frequently asked questions
What is the difference between warfarin and newer blood thinners?
Warfarin needs regular INR blood tests and diet care; newer ones (like apixaban, rivaroxaban) have fixed doses and no routine testing, but are not suitable for every condition.
Can I take painkillers with a blood thinner?
Paracetamol is usually preferred; avoid NSAIDs like ibuprofen unless your doctor agrees, as they add to bleeding risk.
Reviewed by Dr. Sanjay Anbu, MBBS. MedDroid is an AI medical assistant and can make mistakes. It provides general health information, not a diagnosis or medical advice — always consult a qualified clinician. In an emergency, contact your local emergency number immediately.