What the difference between tadalafil and vardenafil?

They both belong to the same class of medicine and essentially work the same.

Levitra (vardenafil) is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5).

Tadalafil (Cialis) is also a Phosphodiesterase type 5 inhibitor

These enhances the effect of nitric oxide at the nerve ending and endothelial cells in the corpus cavernosum by inhibiting phosphodiesterase type 5 in the corpus cavernosum of the penis. This results in vasodilation, increased inflow of blood into the corporus cavernosum, and ensuing penile erection upon sexual stimulation.

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