Can blood-thinners make you bruise more easily?

Blood-thinners are a group of medicines prescribed to many people living with cardiovascular diseases (CVD).

They act on the body’s clotting processes, which are an important part of the healing process.

But, while clotting is vital to stop bleeding after an injury, it can be dangerous when clots form inside arteries or veins already narrowed by CVD.

If this happens the clot can block blood flow to the heart or brain, leading to a heart attack or stroke.

To help prevent this, doctors prescribe blood-thinning medicines to some people with CVD.

What are the different types of blood thinners?

When healthcare professionals talk about ‘blood-thinners’ they are usually referring to 2 groups of drugs: anticoagulants and antiplatelets.

Anticoagulants

These include warfarin and apixaban which thin your blood by interrupting the clotting process.

They are often prescribed to people with some types of atrial fibrillation (AF), an abnormal heart rhythm that can increase the chance of clots forming and causing a stroke.

Antiplatelets

These include aspirin and clopidogrel which stop platelets (a type of blood cell) from making blood clots.

They are often prescribed to people after they’ve had a heart attack or stroke.

Speak to your doctor or pharmacist if you have questions about what medicines you are on.

Why do you bruise more easily on blood-thinners?

If you are on blood-thinners, you can bruise more easily or have worse bruises than usual, because they slowdown blood clotting.

This is because when you knock yourself the smallest blood vessels under the skin (capillaries) can break and start to leak, causing the discolouration you see as a bruise.

With blood-thinners, these tiny broken blood vessels take longer to stop leaking than normal, leaving you with a quicker and/or more severe bruise.

If you are older, you may be at higher risk of bruising anyway, because skin loses its natural elasticity and tone as we age.

For most people, bruising is very manageable and does not cause any long-term problems.

But if you do have bruising that is persistent and comes with other symptoms, you should speak to your doctor as you may need to have your blood-thinner dose adjusted or try a different medicine.

If you have bruising that comes with other bleeding, such as nose bleeds, bleeding gums or blood in your urine or stools, you should also seek medical care.

Pictures: What does bruising look like? 

The bruises caused by blood-thinners look like any other bruises that appear when you knock yourself – they just happen more easily and/or are worse than usual.

Here are 2 pictures of the types of bruises you could get with blood thinning medicines:

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