How Long Does Viagra Last? And How Long Does it Take to Kick In?

How long does Viagra last? How long does it take for it to work?
Medically approved by
Dr Earim Chaudry
Last updated
20th November 2020

Erections aren’t always easy for millions of men in the UK. It’s no big deal. Choose from highly effective, clinically proven solutions.

In 30 seconds…

How long does Viagra take to work? The effects of Sildenafil – the active ingredient in the little blue pill – can usually be felt 30–60 minutes after you’ve taken it. The one-hour mark is when you’ll be at peak power – and most men enjoy the effects for up to 5 hours.

All this depends on lots of different variables, however. For example, Viagra takes a little longer to kick in when taken with or after a heavy, high-fat meal rather than on an empty stomach, for example. You might want to bear this in mind so that you get your timings right.

By the way, while Viagra works great, it does need your input. You’ll need to be sexually aroused to see the difference, for example. If you’ve got that covered, however, have fun!

Viagra: Getting Your Timing Right

Viagra is the most famous treatment for erectile dysfunction around. And, according to studies, it is the most effective one too. Yet, the key to a successful experience with the little blue pill is timing – and that’s what we’re discussing here. 

Viagra – or Sildenafil, as the active ingredient in the drug is known – comes from a class of drugs known as PDE-5 inhibitors. These drugs, which include Tadalafil (Cialis), Vardenafil (Levitra), and Avanafil, tackle an enzyme, called phosphodiesterase type-5, that is responsible for smooth muscle contraction in your penis. By inhibiting this enzyme, more blood can flow to your penis – giving you a better chance of achieving an erection. 

It’s a complex process, and, as a result, you won’t feel Viagra’s effects immediately. So, how long do they take to kick in? And how long can you expect them to last? Let’s take a look. 

How Long Does Viagra Take to Work?

When you’re looking into erectile dysfunction treatments, it’s natural that you’ll want to know how long they take to kick in – and how long you can enjoy its effects for. When you are in the mood, you don’t want to be sitting around twiddling your thumbs waiting for things to get going. So, for both you and your sexual partner, it’s best if you’re fully informed.

Sildenafil works by targeting that enzyme PDE-5. As a result, more blood can flow into your penis, and it becomes easier for you to achieve an erection. For most men, it takes about an hour for Sildenafil to be fully effective, although some people can enjoy its impact only 30 minutes after taking it. That doesn’t mean you’ll automatically get an erection though – you’ll still need to be sexually aroused for this to happen.It’s worth repeating that everything we say about Sildenafil applies to Viagra too. There’s no medical difference between the two drugs – it’s all in the brand name. Whichever one you choose to use, though, aim to take it an hour before sexual activity.

Viagra (Sildenafil)

The little blue pill

It’s the active ingredient in Viagra. MHRA approved and clinically proven to be highly effective by increasing blood flow into the penis.


Best for
One off use
Effective in
8 out of 10 men
Dosage
50 to 100mg

How Long Does Sildenafil Last?

So, you have to wait an hour between popping the pill and peak performance. But how long can you expect the effects of Sildenafil to last? 

Simply, most men experience the active effects of the drug for 2-3 hours. However, it’s not unheard of for it to last as long as 4-6 – and this will change depending on some of the factors outlined below. Generally speaking, though, the amount of the drug that is present in your system halves roughly every 4 hours – and by the time 24 hours have passed, it’s pretty much completely cleared. 

Remember, you won’t just switch on an hour after taking Viagra; you’ll need some sexual stimulation to help things out. However, 2-3 hours gives the vast majority of couples plenty of time to satisfy all of their desires. And, if you’re lucky, you may even find it possible to get it up more than once while you’re under the spell of the drug. 

Do be aware, though, that if you experience any side effects, it’s possible that these can last until the drug is out of your system too.

What Factors Impact the Effectiveness of Sildenafil?

Not everybody’s body is the same – and things can change depending on your build, health, and dinner. Here are a number of external factors that may make Sildenafil a little slower to take effect – or may affect its efficacy overall.

Cialis (Tadalafil)

The weekend pill

Known as the “weekend pill” because it is effective for up to 36 hours, Tadalafil is the generic, unbranded version of Cialis. Clinically proven to help you get an erection when you need it.


Best for
Weekend use
Effective in
Effective in 8 out of 10 men
Dosage
2.5mg, 10mg, 20mg

How Diet Affects Viagra

When we said dinner, it wasn’t a typo. Some things that you consume can have a real impact on the way that you absorb Sildenafil. Here are a couple to look out for. 

Food: Eating a heavy meal, particularly one with lots of high-fat foods, just before taking Sildenafil can make the drug slower to take effect. The body takes longer to absorb the drug when it’s busy metabolising food.

Grapefruit juice: Unfortunately for you fans of citrus fruit, grapefruit juice should be avoided when taking Sildenafil. Drinking it can increase the amount of drug in your bloodstream, making side effects more likely.

Alcohol: Drinking alcohol has a negative impact on blood flow to the genitals, so it reduces the effectiveness of Sildenafil (which is trying to increase blood flow to help you achieve an erection). Alcohol also raises the risk of experiencing side effects from the drug.

Other Factors Affecting Sildenafil’s Effectiveness

It’s not all about food though. Before you take Viagra – or other PDE-5 inhibitors – ensure that you take into account some other variables that affect the drug’s absorption. 

Age: Older men (over 65 years old) might experience the active effects of Sildenafil for longer than the typical 2–3 hours. As you age, your metabolism slows down, so the drug is absorbed more slowly into your body. 

Overall health: Certain health conditions, such as diabetes, MS and some heart conditions, can exacerbate erectile dysfunction. It’s important these are treated and controlled, whenever you look to address an ED problem. 

Other medications: Taking certain other medications at the same time as Sildenafil can impact its effectiveness – so it’s important to make any clinician aware of what treatments you are taking. You should never take Sildenafil alongside other ED medications.

Mental/emotional wellbeing: Many men experience worry and performance-anxiety when beginning ED treatment for the first time, and this is completely natural. So for some men additional support such as counselling might be necessary to maximise treatment success. 

In case Sildenafil doesn’t work perfectly the first time, don’t panic as it’s important to assess its effectiveness over a period of time. Your clinician will help you decide whether you should persevere with the drug, try a higher dose, or choose an alternative treatment.

Important note: Taking more than your prescribed dose of Sildenafil is dangerous, and can potentially cause priapism (a painful constant erection that lasts longer than 4 hours). If this does occur, seek emergency medical treatment.

Tadalafil: The “Weekend Pill”

While we’re here, it is worth mentioning an alternative medical treatment for ED. That’s Tadalafil, the active ingredient in drug Cialis

Tadalafil kicks in about 30 minutes after you take it, while the maximum potential for an erection is about 2 hours after taking. The crucial part, though, is that it remains active in your body for much longer than Sildenafil – for 24-36 hours. That’s why it has the nickname, the “weekend pill”. 

Tadalafil provides a wider window of opportunity. So, if you and your partner are looking for a bit more spontaneity, this option might be a better fit. 

Tadalafil is another PDE-5 inhibitor, meaning that it is affected by similar external factors as Sildenafil. However, Tadalafil is not so much affected by food.

Cialis (Tadalafil)

The weekend pill

Known as the “weekend pill” because it is effective for up to 36 hours, Tadalafil is the generic, unbranded version of Cialis. Clinically proven to help you get an erection when you need it.


Best for
Weekend use
Effective in
Effective in 8 out of 10 men
Dosage
2.5mg, 10mg, 20mg
Viagra (Sildenafil)

The little blue pill

It’s the active ingredient in Viagra. MHRA approved and clinically proven to be highly effective by increasing blood flow into the penis.


Best for
One off use
Effective in
8 out of 10 men
Dosage
50 to 100mg

Key Takeaways

How long Viagra (or Sildenafil) takes to kick in will always depend to some extent on your own body and how it reacts to the drug. However, most men can expect to achieve an erection that is firm enough for sex about 30-60 minutes after taking the tablet. 

Sildenafil typically stays active in your body for up to 4 hours, so sex does take some planning! If you prefer greater spontaneity in your sex life, Tadalafil is an effective, longer-lasting alternative to consider.

ED shouldn’t stop you from enjoying yourself. Finding the right treatment is all it takes to get back to a fulfilling sex life.

Erections aren’t always easy for millions of men in the UK. It’s no big deal. Choose from highly effective, clinically proven solutions.

While we've ensured that everything you read on the Health Centre is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. It should never be relied upon for specific medical advice. If you have any questions or concerns, please talk to your doctor.

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