Drugs to treat erectile dysfunction have updated their safety labels to include an increased risk of low blood pressure when used in patients also taking pulmonary hypertension drugs known as guanylate cyclase (GC) stimulators, such as Riociguat.
The new contraindication will be added to the safety labels of Cialis (tadalafil), Levitra and Staxyn (vardenafil), Stendra (avanafil), and Viagra (sildenafil citrate). The drugs are in a class of medications known as PDE5 inhibitors.
The drugs help men get and maintain erections by relaxing the smooth muscles of the penis and increasing blood flow. They also work through the same genetic pathways that make the skin cancer melanoma more aggressive. This has led researchers to study whether the use of Viagra increases the risk of developing this deadly disease.
Researchers tested this theory with the first approved PDE5 inhibitor, Viagra, and discovered that men who used Viagra were 84 percent more likely to develop melanoma compared to men who had never used the drug. The risk remained in men who had used the drug in the past but discontinued use.
Despite these findings, none of the erectile dysfunction drugs carry melanoma risk warnings.
Erectile dysfunction drugs are not recommended for patients taking alpha-blockers or anti-hypertensives, as the medication can a low blood pressure, known as hypotension, which can be life threatening.