What Dose of Sildenafil Should I Take?

What Dose of Sildenafil Should I Take?
Medically approved by
Dr Earim Chaudry
Last updated
15th July 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…

Sildenafil (generic Viagra) is a treatment for erectile dysfunction (ED) that is available as 25mg, 50mg, and 100mg tablets. One tablet can be taken per day, around an hour before you plan to have sex. The typical starter dose of Sildenafil is 50mg, which is enough to help most men achieve an erection firm enough for sex, alongside sexual stimulation.

If 50mg doesn’t have the desired effect, you may be prescribed the maximum recommended Sildenafil dose of 100mg. Alternatively, if you experience side effects from the 50mg dose you could switch to the lower strength 25mg tablet.

Erectile dysfunction (ED) can be a very frustrating condition, knocking your confidence in the bedroom. If you’re struggling to achieve or maintain an erection when you want to enjoy sex, this can be challenging for you and your partner.

You may find that your ED is only temporary – perhaps caused by stress or personal issues – but if it seems to be sticking around, it’s good to know that effective medical treatments are available. Most likely you’ve already heard of Viagra (or Sildenafil in its non-branded form), but you might be wondering how it works, what doses it comes in, and which dose you should take to start with. Read on to find out.

What Does Sildenafil Do?

Sildenafil belongs to a class of drugs called PDE5 inhibitors – they control the activity of an enzyme with the catchy name phosphodiesterase type-5 (PDE5). When PDE5 is at work, it regulates the blood flow into the penis by influencing the smooth muscle contraction of the blood vessels supplying the penis. This means it is a useful target to potentiate blood flow in men who have erectile dysfunction.

Enter Sildenafil. It temporarily inhibits the action of the PDE5 enzyme. This enables increased blood flow to the penis when you are sexually aroused, which should enable you to achieve and maintain a firm enough erection to have sex.

Important note: Sildenafil is only approved as an ED treatment for men over the age of 18.

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

What Dose of Sildenafil Should I Take?

There are three different Sildenafil dosages available: 25mg, 50mg, and 100mg tablets. Regardless of strength, only one tablet should be taken per day – as it takes 24 hours for the drug to fully leave your body.

It’s recommended that you take the Sildenafil tablet around one hour before you plan to have sex, but it can be taken between 30 minutes and 4 hours before sex if desired. Sildenafil can only start to work once you are sexually stimulated, so after you’ve swallowed the tablet just relax and enjoy some intimate time with your partner. And remember, there may be a delayed onset after a high-fat meal.

Let’s look at the three different doses of Sildenafil and how they compare:

50mg

This is the standard dose of Sildenafil for ED and the one you’re most likely to be prescribed. Research has shown that 50mg is enough for 74% of men to experience improved erections. Note that if you want to buy Sildenafil over the counter then you are restricted to a 50mg dose (available as Viagra Connect).

If you try the 50mg dose and it doesn’t work for you the first time, it’s recommended that you give it a go on a few more occasions before switching to the higher dose or trying a different treatment, such as Tadalafil. In fact, evidence suggests trying a dose on up to 8 separate occasions before increasing your dose or testing out an alternative.

Indeed, you might just need to relax a little more to let the pill get to work. Eating only a light meal and cutting down on alcohol before taking Sildenafil can also help.

25mg

As the lowest recommended dose of Sildenafil, you may be prescribed the 25mg tablet if you’re experiencing any uncomfortable side effects from the 50mg. This reduced strength dose still helps 62% of men get a firmer erection, while side effects may be fewer or less likely to occur.

If you’re over 65 years old and already receiving treatment for liver, kidney, or heart problems, or other age-related conditions, then you could be prescribed the lower Sildenafil dose to avoid problematic interaction with existing medications.

100mg

This is the maximum recommended dose of Sildenafil, which you might be prescribed if the 50mg is not enough to effectively treat your ED. The 100mg tablet doesn’t have a longer-lasting impact than the lower doses, but the effect may be stronger – it has been shown that 82% of men have improved erections with this dosage.

With a higher dose of the drug comes an increased risk of side effects, although these are still typically mild and well tolerated. Possible side effects include nausea, dizziness, headache, blocked nose, and facial flushing. More serious side effects, such as loss of sight or a long-lasting painful erection, are rare. Seek urgent medical attention if these do occur.

Key Takeaways…

When you take Sildenafil as a treatment for ED, the most likely scenario is that the 50mg tablet will be enough to help you achieve a firmer, longer-lasting erection for more satisfying sex. But if you feel that you need a different dose you can always consult with the clinicians at Manual. They may recommend the lower 25mg tablet for fewer side effects or the higher 100mg for greater impact on your erections.

Remember: It’s important that you only take the dose prescribed for you, to keep yourself safe and to experience the most effective treatment for your ED. Treatment for erectile dysfunction is individualised, meaning what works for one person may not work for another. Bear this in mind when researching ED medication and after you’ve started treatment.

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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