What are PDE-5 inhibitors?

Donna Hill Howes, RN
Family Practitioner

PDE-5 inhibitors taken as needed are usually the first drugs prescribed for erectile dysfunction (ED). They are relatively safe, easy to take, and very likely to improve ED symptoms. They improve erections by increasing blood flow in the penis.

PDE-5 inhibitors include avanafil (Stendra), sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra, Staxyn). Avanafil, sildenafil and vardenafil are taken on demand and are active for 4 to 6 hours. Tadalafil can be taken once daily or on demand and is active for up to 36 hours. Although most men respond the first or second time the drug is taken, some men need to take it on 6 to 8 different occasions before it begins to work. 

This answer was adapted from Sharecare's award-winning AskMD app. Start a consultation now to find out what's causing your symptoms, learn how to manage a condition, or find a doctor. 

Continue Learning about Erectile Dysfunction Treatment

What is MUSE therapy for erectile dysfunction?
Jan L. Shifren, MDJan L. Shifren, MD
An alternative to injections is a therapy called MUSE (which stands for "medicated urethral syst...
More Answers
Is erectile dysfunction (ED) treatable?
Honor Society of Nursing (STTI)Honor Society of Nursing (STTI)
Erectile dysfunction (ED) is treatable for most men. The first step is to visit your doctor, because...
More Answers
Can Exercise Help Prevent Erectile Dysfunction?
Can Exercise Help Prevent Erectile Dysfunction?
Are Any New Drugs for Erectile Dysfunction Coming Soon?
Are Any New Drugs for Erectile Dysfunction Coming Soon?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.