Drug interaction

Q: Which 2 commonly used cardiac medicines may interact negatively?

Answer: Aspirin and ACE inhibitors

Effects of ACE inhibitors are attenuated by aspirin.

ACE inhibitors decrease angiotensin II production and inhibit breakdown of bradykinin. Bradykinin stimulates vasodilator prostaglandins via a cyclo-oxygenase–dependent pathway.

Aspirin inhibits cyclo-oxygenase-1 (COX-1), thereby reducing synthesis of vasodilatory prostaglandins.

Above interaction may be of more academic interest. In clinical practice - there are no firm guidelines for use of both drugs simultaneously.