The FDA has notified consumers that Stiff Nights, a product marketed as a dietary supplement for sexual enhancement, contains sulfoaildenafil, an ingredient that can dangerously lower blood pressure and is illegal. Sulfoaildenafil is a chemical similar to sildenafil, the active ingredient in Viagra (from Pfizer). Sulfoaildenafil may interact with prescription nitrates, including nitroglycerin, and cause dangerously low blood pressure.

Stiff Nights is distributed on Internet sites and at retail stores by Impulsaria LLC. It is sold in bottles containing 6, 12, or 30 red capsules or in blister packs containing one or two capsules.

The FDA is advising consumers who have experienced any adverse events from sexual enhancement products to consult their healthcare provider.

For more information visit www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm189300.htm.