Skip to main content

How long does Viagra last and how soon does it work?

Medically reviewed by Sally Chao, MD. Last updated on Aug 22, 2024.

Official answer

by Drugs.com

It takes from 30 minutes to 1 hour for Viagra (sildenafil) to start working, and the effects will last for about 4 hours. It is used to treat erectile dysfunction.

Hardness and duration of erections increase with increased dose. Viagra is given as an oral pill, so it has to be absorbed from your stomach to get into your blood and reach your penis. Studies show that Viagra is rapidly absorbed. It reaches its highest blood level between 30 and 120 minutes after taking it. After 4 hours, half of the Viagra has been broken down by the liver. It continues to decrease over the next 20 hours.

Viagra may take longer to work if you take it after a fatty meal because fat slows down absorption in your stomach. Men over age 65 and men with liver disease or severe kidney disease may have longer effects from Viagra, and the dose may need to be lower.

Viagra works by increasing smooth muscle relaxation in the part of the penis called the corpus cavernosum. When the penis is stimulated, a substance called nitric oxide is released. In a series of steps, nitric oxide is turned into a substance called cGMP. This substance causes smooth muscle relaxation that allows more blood to flow into your penis. Viagra inhibits the breakdown of cGMP, which makes an erection harder and longer lasting. Since this process only starts with stimulation of the penis and the release of nitric oxide, Viagra will not give you an erection without your penis also being stimulated.

Viagra can make your penis stay erect longer, but it may not make you last longer. The time to orgasm and ejaculation may not change. Men with early ejaculation or premature ejaculation may not be helped by Viagra. The American Urological Association does not recommend Viagra as a treatment for premature ejaculation.

Erectile dysfunction has many causes. Viagra is not a cure. It does not increase your desire for sex. The most common cause of erectile dysfunction is decreased blood supply to the penis, which may be a warning of decreased blood supply to other parts of your body. Your doctor may check you for high blood pressure, heart disease and type 2 diabetes.

Erectile dysfunction can also be caused by depression, anxiety and drug or alcohol abuse. Your doctor may help you manage these problems before or in addition to prescribing Viagra.

Related questions

References
  1. U.S. National Library of Medicine DailyMed. July 2021. Available at: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=0b0be196-0c62-461c-94f4-9a35339b4501. [Accessed July 27, 2021].
  2. Krishnappa P, Fernandez-Pascual E, Carballido J, et al. Sildenafil/Viagra in the treatment of premature ejaculation. Int J Impot Res. 31, 65–70 (2019). https://doi.org/10.1038/s41443-018-0099-2.
  3. American Urological Association. What Is Premature Ejaculation? July 2020. Available at: https://www.urologyhealth.org/urology-a-z/p/premature-ejaculation. [Accessed July 27, 2021].
  4. American Urological Association. Erectile Dysfunction. June 2018. Available at: https://www.urologyhealth.org/urology-a-z/e/erectile-dysfunction-(ed). [Accessed July 27, 2021].

Read next

Can I buy generic Viagra online?

The safest way to get a prescription for Viagra is from your doctor. You can even do this over a telehealth call (on the phone or computer) in many cases, although for your first prescription your doctor may want to examine you. Viagra and its generic options can be shipped from verified digital pharmacies in the U.S. Use caution as there are reports of counterfeit online Viagra for sale in the U.S. Continue reading

What is Eroxon?

Eroxon is a topical gel that may be applied to the head of the penis immediately before sexual intercourse. Studies show that 65% of men who used it achieved an erection within 10 minutes and maintained it long enough to have sex. Continue reading

Does Cialis lower blood pressure?

When used alone, Cialis may cause small reductions in blood pressure, but if used with nitrates or guanylate cyclase stimulators like riociguat (brand name: Adempas) your blood pressure may dangerously drop. Do not use these drugs with Cialis. You could get dizzy, faint, or have a heart attack or stroke. Continue reading

Related medical questions

Drug information

Related support groups