Consumption of products with undeclared sildenafil may interact with nitrates found in some prescription drugs (such as nitroglycerin) and may cause a significant drop in blood pressure that may be life threatening. People with diabetes, high blood pressure, high cholesterol, or heart disease often take nitrates. Among the adult male population, who are most likely to use this product, adult males who use nitrates for cardiac conditions are most at risk.

Use of products with undeclared diclofenac may cause increased risk of cardiovascular events, such as heart attack and stroke, as well as serious gastrointestinal damage, including bleeding, ulceration, and fatal perforation of the stomach and intestines. This hidden drug ingredient may also interact with other medications and significantly increase the risk of adverse events, particularly when consumers use multiple NSAID-containing products.