The FDA said International Pharmaceuticals Ltd. of Bradford, Maine, initiated the recall of the tablets because they might contain a potentially harmful undeclared ingredient.

The federal agency said that ingredient -- hydroxyhomosildenafil, an analog of sildenafil -- is the active chemical ingredient of an FDA-approved drug used by some men to enhance sexual performance. The FDA said the use of undeclared chemicals pose a threat to consumers because they might harmfully interact with nitrates found in some prescription drugs and might lower blood pressure to dangerous levels.

The recalled product was sold nationwide in 2-capsule blister packs and 8-capsule bottles.

Consumers can contact CB Distributors in Benoit, Wis., for return instructions or with questions at 800-273-4137, Ext. 3.