APS and Medication

The type of medication you can take to treat other conditions will depend on the type of treatment you are prescribed for APS.


If you are being treated with aspirin then you must let the pharmacist know before you buy any over-the-counter medicines such as pain killers or cough medicine.

Your GP should be aware of any drug interactions with aspirin; in particular, you should not be prescribed medication which can cause gastrointestinal bleeding including non-steroidal anti-inflammatory drugs (NSAIDs) such as:

  • celecoxib
  • diclofenac
  • etoricoxib
  • ibuprofen
  • indometacin
  • naproxen
  • mefenamic acid

Many APS patients are prescribed clopidogrel instead of aspirin as it is gentler on the stomach and does not affect asthmatics. If you are taking clopidogrel, again, the same rules apply as with aspirin: you must let the pharmacist know before buying over-the-counter medicines and you should not be prescribed NSAIDs.

Aspirin and clopidogrel should not be taken together as this increases the risk of gastrointestinal bleeding.

It is safe to take paracetamol and codeine based pain relief if you are taking either aspirin or clopidogrel.


Heparin is used by a number of APS patients including women who must inject with heparin throughout their pregnancy, people taking warfarin who need to raise their INR level and a very small number of patients who are intolerant to warfarin.

Heparin is considered a relatively safe drug with not many contraindications but it should not be used if the person is known to have:


Many APS patients will be on lifelong warfarin and, unfortunately, warfarin reacts with nearly all medicines. Taking other medication as well as warfarin is not a problem, but your INR levels are likely to be affected when you either start or stop other medicines.

Paracetamol and codeine can be taken safely with warfarin for pain relief, although these can affect INR control if taken for long periods. Ibuprofen and aspirin should be avoided as they can cause bleeding, although aspirin can be prescribed by your doctor in certain circumstances.

There is an extremely long list of medications which can interact with warfarin, most notably, antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), anti-depressants, glucosamine, indigestion medicine such as omeprazole, prednisolone and barbiturates. The safest way to check whether there are any drug interactions with warfarin is to ask your doctor or pharmacist, and to read the patient information leaflet that comes with your medicine.

Some medication may cause your INR level to rise, while others will make it decrease; therefore, you should be monitored more closely when you start or stop another medicine to make sure you are reaching your target INR.