Phosphodiesterase Type 5 Inhibitors (PDE5 Inhibitors) Agents Sildenafil (Viagra, Revatio) (see Sildenafil, [[Sildenafil]]) Tadalafil (Adcirca, Cialis) see Tadalafil, [[Tadalafil]]) Vardenafil (Levitra, Staxyn) (see Vardenafil, [[Vardenafil]]) References xxx