Sunday May 3, 2009
Drug -Drug interaction / cardiology

Q: Which two commonly use drugs in CHF (congestive heart failure) - may oppose each other's action?

Answer: Aspirin and Furosemide (Lasix)

Lasix has a direct vasodilator effect and this effect begins within a few minutes after an administration of IV Lasix. This added effect is very useful in treatment of acute pulmonary congestion. But this desirable action can be blocked by nonsteroidal anti-inflammatory drugs including aspirin.

Mechanism of action is not clear but salicylates may inhibit the renal effects of loop diuretics that are mediated by prostaglandins, including increases in sodium excretion, renal blood flow, and plasma renin activity.

Read interesting commentary on this issue: Aspirin Use in Chronic Heart Failure, What Should We Recommend to the Practitioner? (Barry M. Massie, MD - J Am Coll Cardiol, 2005; 46:963-966


References:

1. Jhund PS, Davie AP, McMurray JJ. Aspirin inhibits the acute venodilator response to furosemide in patients with chronic heart failure. J Am Coll Cardiol. 2001;37:1234-1238

2. Effect of combined administration of furosemide and aspirin on urinary urate excretion in man - Journal of Molecular Medicine, Volume 57, Number 23 / December, 1979, 1299-1301