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Sildenafil vs Viagra®: what’s the difference?

Felix Gussone, MD - Contributor Avatar

Reviewed by Felix Gussone, MD, Ro, 

Written by Linnea Zielinski 

Felix Gussone, MD - Contributor Avatar

Reviewed by Felix Gussone, MD, Ro, 

Written by Linnea Zielinski 

last updated: Aug 25, 2022

4 min read

Here's what we'll cover

Here's what we'll cover

Viagra might be the most well-known prescription medication available to treat erectile dysfunction (ED), but that doesn’t mean it’s the only option. Sildenafil is the active ingredient in Viagra (the full name of the drug is sildenafil citrate). It’s also sold without the brand name, sometimes called "generic Viagra" or simply "sildenafil." 

Because these drugs have the same active ingredient (sildenafil), they work the same way in the body. The key differences between Viagra and sildenafil are the dosages available and the price of the drugs, which may differ significantly. 

Viagra is to erectile dysfunction, what Kleenex is to the common cold. They’re household names, but they’re actually brands. They’re each just one of many options available. But while opting for the brand name when you have a runny nose probably won’t cost you more than a couple of extra bucks, the cost of brand-name Viagra can differ significantly from sildenafil or other generic options, sometimes costing a difference of over $50—per pill. A single dose of brand-name Viagra can cost as much as $70, while you can get the generic version for $3 a dose or even less (GoodRx, n.d.). 

Here's what you need to know about these drugs.

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Viagra vs. sildenafil (generic Viagra)

Viagra and its generic version, sildenafil, are just a couple of the prescription medications available to treat erectile dysfunction. These medications differ in a few main ways: generic sildenafil pills may not be produced by Pfizer, the available dosage of each drug may differ, and sildenafil pills cost a lot less.

Although Viagra, or "the little blue pill," reigns supreme in people's minds as the go-to ED medication, you've likely seen other popular names such as Cialis (generic name tadalafil) and Levitra (generic name vardenafil). These ED treatments all belong to a class of drugs called PDE-5 inhibitors, which work by improving blood flow into the penis to give you harder, longer-lasting erections.

Viagra Important Safety Information: Read more about serious warnings and safety info.

Cialis Important Safety Information: Read more about serious warnings and safety info.

What is Viagra?

Viagra is the brand name of sildenafil, which is manufactured and sold by Pfizer. The active ingredient is sildenafil citrate. Viagra comes in three doses: 25 mg, 50 mg, and 100 mg. 

This ED treatment is taken as needed between 30 minutes and 4 hours before you plan to have sex. Though Viagra tablets can start to take effect and help you achieve an erection in just 12 minutes, the medication reaches peak levels in your body after 30–120 minutes (Eardley, 2002). The effects of Viagra usually last in your system for around 6 hours total, but your age, health, and diet all affect how long and how well Viagra will work for you. 

Keep in mind that Viagra doesn’t give you an instant erection. It requires arousal and sexual stimulation to work effectively. Arousal sends blood to the penis, and Viagra works with arousal by keeping the blood flowing once it starts.

Like stories you may have heard, Viagra was initially developed to treat another condition entirely. Pfizer developed sildenafil to treat high blood pressure but noticed something interesting during clinical trials: male study participants had an easier time getting erections. In 1998, the US Food and Drug Administration (FDA) approved the little blue pill for treating ED (McMurray, 2007).

Sildenafil became available as a generic medication in December of 2017. Until then, only two companies (Pfizer and Teva Pharmaceuticals) could produce the drug. This change allowed other companies to manufacture and sell "generic Viagra."

What is generic Viagra?

"Generic Viagra" is typically called sildenafil, and it has the same active ingredient and dosage as Viagra, but it is not sold under the brand name. These generic drugs are bioequivalent, which means they act the same way and produce the same results in the body. A single dose of brand-name Viagra can cost as much as $70, while you can get the generic version for $3 a dose or even less (GoodRx, n.d.). 

Also, the pills themselves might look a little different. The brand name will have “Pfizer” etched into it in tiny letters and usually comes as a diamond-shaped blue pill. The generic can be white or blue and comes in various shapes. Depending on the company manufacturing it, it can have different printing on it. 

What is sildenafil?

Sildenafil is the active ingredient in Viagra and "generic Viagra," but those aren't the only medications that use it.  Under the brand name Revatio, sildenafil is approved by the FDA to treat pulmonary arterial hypertension (PAH), a rare lung disorder (Barnett, 2006).

Now you’re familiar with three versions of sildenafil: Viagra (the brand name), sildenafil (the generic), and Revatio, used to treat PAH. To treat ED, the first two options come in three doses: 25 mg, 50 mg, and 100 mg. Revatio comes in increments of 20 mg and is sometimes used off-label to treat ED.

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Is Viagra or sildenafil right for me?

Viagra and generic Viagra (sildenafil) help combat erectile dysfunction in the same way. They have the same potential side effects, such as low blood pressure, nasal congestion, indigestion, headaches, facial flushing, back pain, sudden loss of hearing or vision, and priapism. 

No matter which drug you use, tell your healthcare provider about any other medications or supplements you’re taking. Viagra and generic sildenafil have the same drug interactions with other medications, like nitrates, for example. That also includes the recreational drug “poppers,” which are sometimes used to relax the muscles around the anus and facilitate anal sex. The combination of nitrates like “poppers” and erectile dysfunction medications like Viagra can lead to a dangerous (potentially fatal) drop in blood pressure.

Whether you choose brand-name or generic, make sure you get your medication from a reputable pharmacy. If someone offers you Viagra without a prescription, it’s likely fake. While fake versions may contain sildenafil, the quantity and quality of the drug are not regulated and could contain much more or less of the active ingredient than it should. Fake pills have also been found to include a range of other undeclared ingredients, like drywall, antibiotics, and even printer ink (FDA, n.d.).  

Choosing between these erectile dysfunction medications largely comes down to cost. Work with your healthcare provider to find a treatment and dose that’s right for you and your budget.

DISCLAIMER

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

Sildenafil (Generic of Viagra)
Erectile Dysfunction

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Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

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Current version

August 25, 2022

Written by

Linnea Zielinski

Fact checked by

Felix Gussone, MD

About the medical reviewer

Felix Gussone, MD - Contributor Avatar

Felix Gussone, MD, Ro

Felix Gussone is a physician, health journalist and a Manager, Medical Content & Education at Ro.

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