PDE5 Inhibitors

The source claims direct nitric oxide support may turn some PDE5 inhibitor non-responders into responders and permit lower drug doses. Viagra, Cialis, and Levitra are described as phosphodiesterase inhibitors. Nitroglycerin cream acts more directly to increase nitric oxide than PDE5 inhibition does, acting faster with fewer systemic side effects but requiring medical supervision. The transcript does not provide specific trial data showing conversion of PDE5 inhibitor non-responders to responders. The effectiveness of PDE5 inhibitors is described as depending on sufficient upstream nitric oxide production. Viagra inhibits the enzyme PDE5, which is involved with smooth muscle of the penis, leading to enhanced nitric oxide activity. PDE5 inhibitor effects depend on inhibiting breakdown of a second messenger activated by nitric oxide. Pharmaceutical PDE5 inhibitors carry a significant side effect profile including headaches, low blood pressure, dizziness, and risk of heart attacks.