Fast Five Quiz: Sildenafil (Viagra)

Mary L. Windle, PharmD


August 04, 2021

Sildenafil is recognized as having low general toxicity with no reproductive toxicity, genotoxicity, or carcinogenic properties. Single doses of as much as 800 mg have been found to result in an increased frequency and severity of adverse effects associated with lower doses. Dialysis does not help clear sildenafil because the drug is highly bound to plasma proteins and is not renally excreted. No antidotes are available for sildenafil.

Clinical studies of higher-than-recommended sildenafil doses showed dose-related increases in the frequency of visual adverse events; however, no clear relationship between dose and maximum blood pressure decreases or clinically significant changes on electrocardiography have been established. Patients who take sildenafil more often than once daily have an increased frequency of transient muscle ache without evidence of muscle damage.

Read more about other warnings and cautions for sildenafil use.

This Fast Five Quiz was excerpted and adapted from the Medscape Drugs & Diseases articles Erectile Dysfunction and sildenafil.

Follow Medscape on Facebook, Twitter, Instagram, and YouTube


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.