If you are currently being treated with any of the following medications, you should not use feverfew without first talking to your healthcare provider.

Blood-thinning medications
Feverfew can inhibit the activity of platelets (a substance that plays a role in blood clotting), so individuals taking blood-thinning medications (such as aspirin and warfarin) should consult a healthcare practitioner before taking this herb.

NSAIDs
Although specific interactions between feverfew and conventional medications have not been adequately researched, a potential interaction with non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, has been identified and may result in decreased effectiveness of these medications. The opposite may be true as well – namely, that NSAIDs can render feverfew ineffective.