What Does Viagra Do?

Medically approved by
Dr Earim Chaudry
Last updated
11th November 2020

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It is the most famous of the treatments for erectile dysfunction, a condition that affects many men of all ages. But what does Viagra do?

Viagra is powered by its active ingredient, Sildenafil, a medication from the class of drugs known as PDE5-inhibitors. These drugs target the enzyme, PDE5, that is responsible for smooth muscle contraction in the blood vessels supplying the penis. By inhibiting it, more blood can flow to where it is needed.

This little mechanism improves your chances of achieving and sustaining an erection. But it can’t do it all on its own: you’ll still need to be aroused.

Introducing Viagra (Sildenafil)

Originally designed by Pfizer as a treatment for high blood pressure and heart disease, Viagra has become one of the most famous – and most counterfeited – drugs in the world. That’s because it is now used to treat erectile dysfunction (ED), a condition that affects millions of men in the UK alone.

But what does Viagra actually do? In this article, we’re investigating the mechanisms that enable Viagra – and its active ingredient, Sildenafil – to get to work. It all begins with your blood flow, but it can also boost your sexual confidence, too.

However, if we’re talking about what Viagra does, we need to mention what it doesn’t do. While Viagra works a treat for tackling ED, many people attribute it with more power than it actually has. Let’s take a look at all you need to know.

What Does Viagra Do?

Viagra – or, more specifically, Sildenafil – is one of a group of drugs known for their efficacy in treating erectile dysfunction. These, including Tadalafil (or Cialis), Vardenafil (or Levitra), and Avanafil, are known as PDE5-inhibitors, and they all work in a similar way.

What PDE5 inhibitors do is target the enzyme, phosphodiesterase type 5 (PDE5), that is responsible for smooth muscle contraction in the blood vessels supplying your penis. By inhibiting this enzyme, blood flow is improved. And, the more blood flowing down there, the better the chances that you’ll achieve an erection – or sustain one long enough to have sex.

Something that needs to be stressed, however, is that this process requires you to be aroused. Erections happen because of signals from the brain that promote the engorgement of your penis with blood. While the little blue pill can do an awful lot, it does need some sort of sexual stimulation to kickstart the process.

How Effective is Viagra?

What Viagra does it does very well indeed. Studies suggest that 87% of men who take Sildenafil have erections hard enough to have sex. Similarly, people taking Sildenafil long-term were found to have a success rate of 82% – with over three quarters of men having successful sex every time they tried.

In this way, you can depend on Sildenafil to do what it is designed to do. And, out of all of the PDE5-inhibiting erectile dysfunction treatments, it may well be the best. According to a review of 82 different studies, Viagra emerged as the most reliable of all the similar drugs available.

However, it’s important to note that Viagra lasts for up to 8 hours, after kicking in about 30 minutes after you’ve taken it. While this is sufficient for any sexual activity, some people want a bit of extra flexibility. If that’s you, you may be tempted by another ED treatment, Tadalafil, which is designed to keep you going all weekend.

Side Effects of Viagra

It’s important to remember that, like many other medicines, Viagra can have side effects. 

The drug works by improving your blood flow, which can cause drops in blood pressure. If you have a low blood pressure already, then you may be more susceptible to the common side effects.

These include dizziness and faintness, as well as indigestion, a stuffy nose, and sometimes changes to your vision. In the vast majority of cases, these are temporary and mild, although they may affect your sexual performance. If they don’t disappear within a couple of hours, you should seek medical advice.

One of the most notorious serious side effects of Viagra is priapism, a painful erection that lasts potentially for hours. While these are really uncommon, you should seek the immediate attention of a healthcare provider if you feel you are experiencing one.

Finally, it is important to say that, due to the way that Sildenafil works, people with medical conditions – including pulmonary arterial hypertension, high cholesterol, or heart conditions – should talk to their clinician before taking the drug.

What Viagra Doesn’t Do

So, that’s what Viagra does. But it’s worth clarifying what Sildenafil doesn’t do too. As with so many things about which we’re all a little coy, there are many myths associated with the drug. Yet, it’s important to know what you can reliably expect from the little blue pill – so that you’re not disappointed.

Here are some myths – or, at least, misunderstandings – about what Sildenafil does: 

Does Viagra Make Your Penis Bigger?

One of the popular myths about Viagra is that it will make your penis bigger. Unfortunately, it doesn’t do that – at least not in the sense that you probably mean.

Sildenafil does not make penises permanently larger. However, it can help you to reach your full-size potential. A common symptom of erectile dysfunction is not being able to become fully hard. Viagra can help with that – and, in that sense at least, it will make you bigger. 

Does it Cure Premature Ejaculation?

Remember that Viagra is specifically a treatment for erectile dysfunction. It is not licensed as a treatment for premature ejaculation – the condition in which men reach orgasm much more quickly than the norm – and should not be used as such.

Importantly, though, Sildenafil can help you last longer in bed – but only if you are finishing too early because you cannot sustain an erection. In this case, Viagra’s got your back.

Will Sildenafil Boost My Libido?

Fundamentally, Viagra increases blood flow to where you need it. It is a physiological cure for erectile dysfunction, and, as such, will not strictly give your libido a boost.

However, the drug has been shown to give men’s self-confidence a new lease of life and to improve their satisfaction in their sexual relationships, too. In this way, it might make you more open to sexual intimacy, reduce performance anxiety, and feel more in control when you need to be.

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

So, what does Viagra do? As a treatment for erectile dysfunction, Sildenafil inhibits the enzyme responsible for smooth muscle contraction in the penis – and increases blood flow as a result. In this way, it helps about 85% of men to achieve an erection.

But that’s not all it does. Viagra boosts confidence, self-esteem, and sexual satisfaction too. So, if you’re struggling with erectile dysfunction, it may well be the support you need.

References

  1. Pioneering Research from Boston University -Counterfeit Viagra Is a Problem, Muhammad Zaman’s book Bitter Pills examines the world of counterfeit and substandard drugs: http://www.bu.edu/articles/2018/counterfeit-viagra-is-a-problem/

  2. Culley C CarsonArthur L BurnettLaurence A LevineAjay Nehra (2002). The efficacy of sildenafil citrate (Viagra) in clinical populations: an update: https://pubmed.ncbi.nlm.nih.gov/12414330/

  3. A T GuayJ B PerezJ JacobsonR A Newton (2002). Efficacy and safety of sildenafil citrate for treatment of erectile dysfunction in a population with associated organic risk factors: https://pubmed.ncbi.nlm.nih.gov/11545291/

  4. Stanley E Althof, PhD, Michael P O’ Leary, MD, MPH, Joseph C Cappelleri, PhD, MPH, Sidney Glina, MD, PhD, Rosie King, MB, BS, FACSHP, Li-Jung Tseng, PhD, and Jessica L Bowler (2006). Self-Esteem, Confidence, and Relationships in Men Treated with Sildenafil Citrate for Erectile Dysfunction: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1831645/

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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