Loading...
Three FDA-approved phosphodiesterase-5 (PDE-5) inhibitors (sildenafil, vardenafil, and tadalafil) are now available for treating male erectile dysfunction (ED). These agents are safe for patients with cardiovascular disease but can interact with nitrate medications, which stimulate the same vasodilatory messenger that PDE-5 breaks down.
Tadalafil (Cialis) has a longer half-life than the better-studied sildenafil (Viagra) does (17.5 hours vs. about 4 hours), prompting researchers to examine the time course of nitrate interaction with tadalafil. In a multicenter, manufacturer-funded study, 166 men without ED were randomized, in double-blind fashion, to tadalafil (20 mg daily) or placebo for 1 week and then, at various times up to 96 hours afte…