Phosphodiesterase inhibitor used for erectile dysfunction

Ref: KD Tripathi, 7th ed. pg. 303* Sildenafil is an orally active drug for treatment of ED. Sildenafil acts by selectively inhibiting PDE-5, causing increase in cGMP and enhancing Nitric Oxide action on corpus cavernosum.* Amrinone and Milrinone are PDE-3 inhibitor and are also called inodilators. They are used in CHF.* Tamoxifen is a selective estrogen receptor modulator, used in breast cancer.