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Last updated June 30, 2020. 2 minute read

How can I buy Viagra? There's only one safe and legal option

The FDA requires a prescription for Viagra—either the brand-name drug or generic medication. Obtaining Viagra without a prescription and consulting with a healthcare provider is a risky proposition that can have real health risks.

Self Written by Michael Martin
Reviewed by Dr. Mike Bohl, MD, MPH

How can you buy Viagra?

The FDA requires a prescription for both brand-name and generic Viagra.

Viagra and other ED medications can have side effects including headache, facial flushing, nasal congestion, stomach upset, backache, and, rarely, temporary impaired color vision (men with the eye condition retinitis pigmentosa should check with their healthcare providers before using those prescriptions).

It’s a good idea to consult a healthcare provider at the first sign of ED, because it might be caused by a serious underlying medical condition, including heart disease, high blood pressure (hypertension), diabetes, or depression. A healthcare provider should take your full medical history before prescribing Viagra.

Vitals

  • Viagra (sildenafil) is an oral medication prescribed to treat erectile dysfunction (ED).
  • Viagra is part of a group of drugs known as PDE-5 inhibitors.
  • Viagra works by blocking an enzyme that, through a series of reactions, causes blood to flow out of an erect penis.
  • The FDA requires a prescription for Viagra—either the brand-name drug or generic medication.

Counterfeit Viagra

Not surprisingly, Viagra is one of the most counterfeited drugs in the world. (Anyone who’s accidentally wandered into a fusillade of online pop-up ads touting Viagra prescriptions for cents on the dollar can attest to this.)

When you buy an unregulated substitute for the real thing, you literally don’t know what you’re getting. In 2011, Pfizer, the manufacturer of Viagra, investigated counterfeits by buying them online and testing their contents. Some of the pills they received contained blue printer ink, amphetamines (“speed”), an antibiotic called metronidazole, too much of the active ingredient sildenafil (or not enough)—and drywall (Pfizer, n.d.). 

Hopefully, we’ve made the point: Obtaining Viagra without a prescription and consulting with a healthcare provider is a risky proposition that can have real health risks.

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What is Viagra?

Viagra is the brand name of sildenafil, a prescription medication that treats erectile dysfunction (ED). The active ingredient is sildenafil citrate.

Viagra comes in three doses: 25 mg, 50 mg, and 100 mg. This is taken as needed, between 30 minutes and four hours before sexual activity.

How does Viagra work?

Viagra is part of a class of drugs known as PDE-5 inhibitors. These do what it says on the tin: They inhibit the body’s production of PDE-5, an enzyme that tells the body to make an erection subside.

PDE-5 (phosphodiesterase type-5) is an enzyme that breaks down a substance called cGMP, which causes vasoconstriction, or the narrowing of blood vessels. High levels of PDE-5 are found in blood vessel walls, including blood vessels in the penis.

Viagra blocks PDE-5, so elevated cGMP levels remain. This keeps blood vessels relaxed, encouraging blood flow to the penis and producing an erection.

Viagra helps you achieve an erection 30 minutes to one hour after taking it, although, in one study, some patients saw an effect in as little as 12 minutes (Eardley, 2002). It can last in the bloodstream for up to four to five hours. But several variables affect the exact amount of time it will work, including your age and health.