Key takeaways:
Viagra (sildenafil) is a prescription medication that treats erectile dysfunction (ED). It works by relaxing smooth muscles and arteries in your penis to help you achieve and maintain an erection.
Viagra’s effects typically last for at least 4 hours. But it can stay in your system for up to 20 hours (close to a day).
Avoid taking Viagra at the same time as nitrates such as nitroglycerin (Nitrostat). This combination can cause a dangerous drop in blood pressure.
Viagra is available as a lower-cost generic called sildenafil. GoodRx can help you save over 95% off the average retail price at certain pharmacies. Another option is using GoodRx for ED to get generic Viagra delivered directly to your door starting at $18 per month.
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Sexual health is an important part of well-being. Many television shows, movies, and podcasts openly discuss this topic. But in reality, addressing sexual health problems — such as erectile dysfunction (ED) — can sometimes feel uncomfortable to discuss with healthcare professionals.
Thankfully, many medications can manage ED. Viagra (sildenafil) is one popular medication that treats ED in adult men. It’s available as a prescription-only tablet in both brand and generic versions. The typical Viagra starting dose is 50 mg (1 tablet) by mouth 30 minutes to 4 hours before sex.
If you’re new to Viagra, it’s helpful to know how long it stays in your system and how to maximize its use. Knowing the answers to the top Viagra frequently asked questions can help you have a positive experience with the medication.
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1. How long does Viagra stay in your system?
As a general rule, it can take close to a day for Viagra to fully leave your body. This is related to the medication’s half-life. A medication’s half-life is an estimation of the time it takes for the starting dose to be lowered by half in your body.
Viagra’s half-life is about 4 hours, which is typically how long it’s effective for. It takes at least 4 to 5 half-lives for a medication to completely leave the body. So Viagra should be mostly gone after about 16 to 20 hours.
Factors that affect how long Viagra lasts
Many factors can affect how long Viagra lasts. A few of them include:
Metabolism: Your body’s metabolism helps process medications. If you naturally have a faster metabolism, Viagra may wear off sooner. A slower metabolism can make it last longer. This is one reason the effects can vary from person to person.
Age: Your metabolism tends to slow down as you get older. If you’re 65 or older, Viagra may stay in your body longer, which can raise the risk of side effects. As a result, if you’re 65 or older, you’ll likely start with a lower dose of 25 mg.
Diet: When you eat a high-fat meal shortly before taking Viagra, your body absorbs the medication more slowly. That doesn’t make it last longer — it just takes longer to kick in.
Health conditions: Your body can respond differently to Viagra if you have certain health conditions, namely liver, kidney, or heart problems. You may need a lower dose of 25 mg. In some cases, it may not be safe for you to take Viagra at all.
Other medications: Certain medications can interact with Viagra and cause potentially dangerous side effects. For example, taking Viagra with the antibiotic erythromycin (Ery-Tab) can raise the amount of Viagra in your body. We’ll discuss interactions in more detail later.
2. How long can you take Viagra?
There’s not a specific “end date” for taking Viagra. But there are some mixed results about how long Viagra is effective for. One study found Viagra’s effectiveness started to wear off after about 2 years of consistent use. But a different long-term study found that Viagra was still safe and effective after 4 years.
It’s best to have a conversation with your healthcare professional about how long you should take Viagra for. Tell them if you notice your Viagra not working as well as it used to. They may recommend switching to a different ED medication that you take every day, like Cialis (tadalafil).
3. How does Viagra work?
Viagra belongs to a group of medications called phosphodiesterase-5 (PDE5) inhibitors. It works by helping nitric oxide — a natural chemical in the body — relax smooth muscles and widen blood vessels. This helps improve blood flow to your penis.
If you have more blood flow to the penis, you’re more likely to get and maintain a harder erection. Viagra typically starts to kick in within 30 minutes to 1 hour of taking it.
4. Does Viagra affect how long you last (premature ejaculation)?
While Viagra isn’t FDA approved to treat premature ejaculation, some studies suggest it may be helpful for this use. PDE5 inhibitors like Viagra could make you last a few minutes longer. Premature ejaculation happens when you ejaculate within 2 minutes of penetrative sex (or faster than you want to).
Taking Viagra in combination with a selective serotonin reuptake inhibitor (SSRI) — like sertraline (Zoloft) — may also help you last longer during sex. SSRIs raise serotonin levels which may help delay ejaculation time.
Other options for erectile dysfunction (ED): Learn how Viagra (sildenafil) compares to Cialis (tadalafil) and other popular medications for ED.
Viagra isn’t safe for everyone: Certain people shouldn’t take Viagra at all. Here’s what to know.
Taking Viagra without ED: There are risks to taking Viagra off-label if you don’t have ED.
You can also try certain techniques on your own to see if they help. These include the stop-start technique or the squeeze technique.
5. Should you take Viagra instead of Cialis?
Not necessarily. Viagra and Cialis are both effective ED medications. One isn’t better than the other. The best one for you may boil down to your personal preferences and insurance coverage.
If you’re planning to take an ED medication occasionally, Viagra is a good option to start with. It’s meant to be taken just before sexual activity and its effects last for about 4 to 8 hours at a time. For daily use, Cialis might be a better choice. Each Cialis dose is effective for up to 36 hours and allows you to be more spontaneous with sex.
Another difference between Viagra and Cialis is whether you need to take them with food. Viagra works better when it’s taken on an empty stomach. Food can delay the absorption of Viagra. You can take Cialis with or without food.
6. Will Viagra improve my sex drive?
No, Viagra won’t improve your libido (sex drive). You must be sexually aroused for Viagra to work. Once you become aroused, Viagra enhances nitric oxide’s effects, increasing blood flow to your penis.
7. Are natural or over-the-counter Viagra alternatives available?
Technically, yes. But there’s limited information available about the safety and effectiveness of over-the-counter (OTC) Viagra alternatives.
It’s important to be cautious of OTC products that claim to treat ED. The FDA has issued warnings that these products may contain hidden ingredients that could be dangerous to your health. In fact, one FDA study found that over 300 ED products contained ingredients not listed on the label.
That being said, L-arginine is an oral supplement that may help with mild-to-moderate ED. It’s an amino acid that can also be found in your diet through foods such as red meat and dairy. Your body changes L-arginine into nitric oxide, which improves blood flow.
But L-arginine does have side effects you should be aware of. Diarrhea and low blood pressure are two potential issues. And if you have kidney disease or experienced a heart attack recently, it’s best to avoid L-arginine. A healthcare professional can tell you more about the safety of OTC products marketed for ED.
8. Viagra for women: can they take Viagra too?
Sometimes. Viagra isn’t FDA approved for women, but it’s sometimes prescribed as an off-label treatment. Some research suggests that Viagra tablets may benefit women who struggle with arousal or orgasm.
There may be another Viagra alternative in the future, too. Sildenafil, the active ingredient in Viagra, was enrolled in a phase 2 study as a topical cream for premenopausal women with arousal difficulties. Initial results suggest enhanced sexual function with sildenafil cream.
For women who haven’t experienced menopause, there are two FDA-approved medications to help with low sex drive: Addyi (flibanserin) and Vyleesi (bremelanotide). You should speak with a healthcare professional if you want to learn about more options or resources that can help improve your sexual health.
9. Who shouldn’t take Viagra?
There are a few situations where you should avoid taking Viagra.
One of those situations is when you’re already taking an interacting medication. Certain medications can cause dangerous interactions with Viagra. For instance, nitrates like nitroglycerin (Nitrostat) and isosorbide mononitrate (Monoket) pose serious issues with Viagra. Both nitrates and Viagra widen blood vessels. You may develop severe hypotension (low blood pressure) if you take them together.
Viagra’s labeling recommends avoiding this combination altogether. If you take Viagra, separate your Viagra dose from your nitrate dose by at least 24 hours. Guanylate cyclase stimulators like Adempas (riociguat) have a similar interaction with Viagra.
Your healthcare professional may also recommend avoiding Viagra if you have certain health conditions. For example, they’ll be hesitant to prescribe it if you’ve had a heart attack or stroke within the last 6 months. Taking Viagra if you have these heart conditions could be dangerous, as they could cause dangerous blood pressure and heart changes.
Viagra can also cause vision issues, such as color changes and blurred vision. It’s important to have your eyes checked occasionally while taking Viagra.
What’s more, if you’re allergic to the medication or any of its inactive ingredients, you shouldn’t take it.
10. Are there ways to save on Viagra?
There are ways to save on Viagra, with or without prescription insurance. It’s available as both a brand-name and generic medication.
Save with GoodRx: GoodRx can help you save over 95% off the average retail price of the generic version. Generic Viagra’s price for thirty 50 mg tablets at certain pharmacies is as low as $11.70 with a free GoodRx discount.
Save with GoodRx for ED: Get generic Viagra delivered directly to your door starting at $18 per month.
Save with a copay savings card: If you have commercial insurance, you may be eligible to save up to 50% off your copay for brand-name Viagra using a savings card from the manufacturer.
The bottom line
Viagra (sildenafil) is a phosphodiesterase-5 (PDE5) inhibitor that treats erectile dysfunction (ED). It’s typically effective for 4 to 8 hours at a time, but it can stay in your system for up to 20 hours. Certain factors — such as older age — can make Viagra stay in your body for longer. This timeframe is especially important to keep in mind if you’re taking interacting medications, such as nitrates or Adempas (riociguat).
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References
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