How Long Does Viagra Last?

Medically reviewed by Lindsay Cook, PharmD

Erectile dysfunction (ED) is a common but highly frustrating medical condition. In the United States alone, it is estimated that more than 30 million Americans assigned male at birth experience ED.

Defined as the inability to maintain an adequate erection for sexual intercourse, ED can be the byproduct of a more serious psychological or physical condition, such as a sleep disorder or hyperglycemia (high blood sugar).

Often, the inability to perform sexually can negatively affect a person's mental health and impact the quality of relationships.

As a result, many will turn to Viagra (sildenafil) as a quick, effective solution for their ED. Viagra can last for about four hours or more in some people and should be taken 30 minutes to an hour before sexual activity.

This article will discuss Viagra's ability to work quickly, its current safety concerns, alternative treatments, and more.

How Does Viagra Work?

Viagra, containing the active ingredient sildenafil, belongs to a class of drugs called phosphodiesterase (PDE)-5 inhibitors.

An erection happens when a series of chemical processes is triggered by nerve stimulation, leading to muscle relaxation that allows blood flow to the penis.

PDE-5 is a molecule that prevents or eliminates erections. This molecule is inhibited by drugs like Viagra, making it easier to get an erection and keep it for longer.

How Long Does Viagra Take to Start Working?

Taking Viagra one hour before sexual activity is recommended for most people, but you can take it anywhere from 30 minutes to four hours prior.

Maximum drug concentration, meaning when Viagra is most present in the bloodstream, is reached 30 minutes to two hours after taking Viagra, with one hour being the average time.

Keep in mind that sexual stimulation is required for Viagra to work. It will not spontaneously cause an erection.

How Long Does Viagra's Effects Last?

The effects of Viagra usually last around four hours but may be longer in some individuals, based on your metabolism and the dose you take; this is why you don’t want to take Viagra more than four hours before sexual activity.

Will Viagra Keep Me Erect After I Ejaculate?

While it probably will not keep you erect after you ejaculate, Viagra may help decrease the refractory period, the time after ejaculation when you have difficulty getting an erection again.

This time may be as short as a few minutes in younger people and as long as a few hours or days in older adults.

How Long Does It Take for Viagra to Leave the System?

Viagra will take about 16 to 20 hours for Viagra to be cleared from your body.

This does not mean that Viagra will work for 16 to 20 hours.

There may still be a minimal amount of the drug left in your bloodstream by this time, but not enough for it to continue working to promote erections.

Inhibitors to Effective Viagra Use

Consumption of particular food or drinks or certain behaviors may affect Viagra's ability to work effectively, including the following:

Heavy, High-Fat Meals

Don’t take Viagra on a full stomach—especially if you’ve eaten a heavy meal high in fat. This may take Viagra longer and not work as well as it should.

Drinking Alcohol or Taking Drugs

It’s OK to drink alcohol in moderation with Viagra, but drinking may make it more challenging to get an erection, especially after drinking a lot.

Alcohol is a depressant that affects many systems in the body, including those involved in producing an erection. Recreational drugs, including cannabis (marijuana), may also worsen ED symptoms.

Correct Dosing and Timing

Remember that the ideal time to take Viagra is 30 minutes to one hour before sexual activity.

If you take the pill exactly as prescribed and it isn’t working, speak with your healthcare provider about adjusting the dose or trying a different prescription medication.

General Health

A holistic approach to health is important to maximize the effectiveness of Viagra, and it may even help your sexual performance without Viagra use.

Because anything that reduces blood flow can hinder erections and maintain heart health. Get at least 150 minutes of physical activity weekly, maintain a healthy weight, and stop smoking.

Viagra Side Effects

Common side effects of Viagra include headache, flushing, indigestion, dizziness, and nausea.

More serious side effects to watch out for include an erection lasting four hours or longer or a painful erection that lasts six or more hours, called priapism.

These should prompt you to seek immediate medical attention, as not doing so could lead to penile tissue damage and potentially a permanent loss of potency.

Will Viagra Stop Me From Ejaculating?

The effects of Viagra on ejaculation are unclear.

One study has shown, however, that Viagra may improve premature ejaculation, meaning you will last longer during sexual activity.

However, it hasn’t been determined whether improvement in premature ejaculation is from Viagra's overall effects that, in turn, lower performance anxiety.

Notify your healthcare provider if you experience difficulty with ejaculation while taking Viagra. If you have an erection that lasts longer than four hours, seek immediate medical care.

Is Viagra Safe in Females?

Viagra does increase blood flow to the genitals, but it hasn’t been proven to improve the female sex drive. Also, the Food and Drug Administration (FDA) has not approved it for use in females.

Viagra isn’t necessarily harmful to females, apart from the risk of side effects, but it may not make much difference in your sex drive or enjoyment of sex compared to going without it.

If you’re a female experiencing low libido or not enjoying sex, speak to your healthcare provider, as there are other, more proven solutions.

Alternatives to Viagra

PDE-5 inhibitors are the most common drug to treat erectile dysfunction.

Other prescription medications in the PDE-5 inhibitor class besides Viagra include the following:

• Generic vardenafil is similar to Viagra and may last up to five hours.

• Cialis (tadalafil) is a longer-lasting PDE-5 inhibitor will allow males to achieve erections up to 36 hours after a dose. It can also be taken daily rather than as needed.

• Stendra (avanafil) is the newest PDE-5 inhibitor currently available as a brand-name product. It is faster-acting than other drugs in the class and has a relatively milder side effect profile.

Devices and alternative treatments that can help with ED include pumps and implants, counseling efforts, and shock wave therapy.

Summary

Viagra is a PDE-5 inhibitor, a pill taken by mouth that helps you get an erection and keep it longer. It works by blocking the molecule that normally gets rid of an erection.

Take Viagra about one hour before sexual activity and only once per day unless otherwise instructed by your healthcare provider.

Viagra will last at least four hours and as long as 12 hours in some individuals.

You may get multiple erections during this time, but an erection should never last longer than four hours. This is called priapism, a medical emergency for which you should seek immediate care.

Other common side effects include headache, flushing, dyspepsia or bloating, abnormal vision, and stuffy nose or cold-like symptoms.