How Does Viagra Work?

It's an oral treatment for erectile dysfunction

Viagra interferes with the chemical that lets blood leave an erect penis

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Disclaimer: This information isn’t a substitute for professional medical advice, diagnosis, or treatment. You should never rely upon this article for specific medical advice. If you have any questions or concerns, please talk to your doctor.

How Viagra Works: Your Erection “Off-Switch”

Erections are surprisingly complicated. Getting an erection involves your heart, blood vessels, hormones, nerves, and even your mood to be in harmony. This process essentially boils down to increasing blood flow to the penis and trapping that blood flow in special erectile tissues.

An erect penis contains up to 8x more blood than a flaccid penis

Eventually, this trapped blood gets released, the erection ends, and blood flow returns to normal. Viagra works by interfering with the process that lets blood leave an erect penis.

How Long Should an Erection Last?

PDE5 is the enzyme that’s responsible for “turning off” erections. It works by relaxing muscles and veins in the penis enough to let blood flow return to normal. Usually, that’s a good thing. If an erection lasts more than a few hours it can damage the penis. (That’s why ED medication has a warning about erections “lasting longer than 4 hours”).

Erectile Dysfunction occurs when PDE5 makes it difficult to get or maintain an erection. Sildenafil, the active ingredient in Viagra, is part of a family of drugs called “PDE5 inhibitors.” PDE5 inhibitors stop PDE5 from working, naturally tipping the scales back in favor of your erection.

Erectile Dysfunction: How Erections Work

Understanding PDE5 and blood flow is a big part of how erectile dysfunction medications work. But overactive PDE5 isn’t the only thing that can cause erectile dysfunction (ED). In fact, ED is often a sign of a more serious underlying health problem like:

  • Heart disease
  • High blood pressure
  • Low testosterone
  • Diabetes
  • High cholesterol
  • Nerve damage
  • Depression
  • or even sleep apnea

Click here for more detailed info on how erections work and some of the most common causes of erectile dysfunction.

Important Safety Information

Treatment with PDE-5 inhibitors is not safe for everyone. For example, people on drugs called “nitrates” for certain heart conditions and riociguat for the treatment of pulmonary arterial hypertension cannot take Viagra. To learn more, see IMPORTANT SAFETY INFORMATION about Viagra.

Talk to you Doctor Before Starting a Treatment for ED

Talk to your doctor or start your online visit today if you’re experiencing any symptoms of ED, including softer erections or difficulty getting an erection. Find out if ED is the result of something more serious, and if ED treatment options are safe for you.

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