phosphodiesterase

enzyme

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Last updated

July 19, 2026

Quick Summary

Phosphodiesterase is an enzyme that acts on diesters, specifically hydrolyzing one of two ester groups. It is also known as a phosphatase.1

A specific type, phosphodiesterase-5 (PDE-5), plays a crucial role in the penis's erectile tissue. During sexual arousal, nitric oxide triggers the formation of cGMP, which allows blood flow for an erection. PDE-5 breaks down cGMP. Therefore, PDE-5 inhibitors, like Viagra and Levitra, block this enzyme, maintaining cGMP levels and aiding in achieving or preserving an erection. These inhibitors can have side effects and are not suitable for everyone, particularly those taking nitrate drugs.2

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asthma
Treatment and management of asthma
Agents that block enzymes called phosphodiesterases, which are involved in mediating airway constriction and inflammation, are in clinical trials. These drugs are designed to be long-lasting—administered once per day via inhalation—and are expected to be safer than traditional medications, which may cause cardiovascular damage. A prolonged asthma attack that does…
Read More
Agents that block enzymes called phosphodiesterases, which are involved in mediating airway constriction and inflammation, are in clinical trials. These drugs are designed to be long-lasting—administered once per day via inhalation—and are expected to be safer than traditional medications, which may cause cardiovascular damage. A prolonged asthma attack that does…
Read More