Can I take Metformin and Clopidogrel together?

Why this happens

Clopidogrel and metformin are processed by different pathways in the body. Clopidogrel is an antiplatelet medicine that works on blood cells to prevent clots, while metformin works on the liver and muscles to improve insulin sensitivity. They do not interfere with each other's absorption, metabolism, or effectiveness.

What you should do

You can safely take these two medicines together as prescribed by your doctor. However, always monitor your blood sugar levels regularly and watch for any unusual bruising or bleeding, which are side effects of clopidogrel. If you are scheduled for surgery, ensure your doctor knows you are taking clopidogrel, as it may need to be paused.

Important precautions

Bleeding risk

Clopidogrel thins your blood. You are at a higher risk of serious bleeding. Seek urgent medical help if you have a fall or head injury, or if you notice signs of internal bleeding such as black, tarry stools or vomiting blood. You must tell your surgeon or dentist that you are taking clopidogrel before any procedure, as you may need to stop taking it temporarily to prevent excessive bleeding.

Lactic acidosis

In rare cases, metformin can cause a serious build-up of acid in the blood. Seek immediate medical attention if you experience severe vomiting, stomach ache, muscle cramps, or a general feeling of being very unwell with extreme tiredness.

Severe kidney problems

You must not take metformin if you have severe kidney failure. Your doctor should check your kidney function before you start and at least once a year while taking it.

Severe dehydration or infection

If you develop severe vomiting, diarrhoea, or a high fever, you must temporarily stop taking metformin and contact your doctor to prevent kidney strain.

Food and drink warnings

Alcohol

It is best to avoid or strictly limit alcohol while taking metformin. Drinking alcohol can increase the risk of a rare but serious condition called lactic acidosis (a build-up of lactic acid in the blood) and can also increase the risk of low blood sugar (hypoglycaemia).

It is best to avoid or strictly limit alcohol while taking clopidogrel. Both alcohol and clopidogrel can irritate the stomach lining and increase the risk of internal bleeding, particularly in the stomach and intestines.

Vitamin B12 absorption

Long-term use of metformin can prevent your body from absorbing enough vitamin B12 from your food. You may need to have your B12 levels checked by your doctor or take a supplement if you develop symptoms like extreme tiredness or a sore tongue.

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.