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Sildenafil tablets (25mg, 50mg, 100mg)
Sildenafil tablets (25mg, 50mg, 100mg) Product information
£5.89 (£1.47 per tablets)
| 25mg | 50mg | 100mg | |
|---|---|---|---|
| 4 tablets | £5.89 | £8.19 | £8.19 |
| 8 tablets | £9.49 | £13.79 | £14.89 |
| 16 tablets | £14.98 | £22.79 | £25.85 |
| 32 tablets | £31.99 | £41.35 | £41.98 |
| 64 tablets | £40.98 | £57.49 | £62.98 |
What is Sildenafil?
Sildenafil tablets (25mg, 50mg, 100mg) are a trusted treatment for erectile dysfunction (ED). They help increase blood flow to the penis during sexual stimulation, making it easier to get and keep an erection firm enough for sex.
Available in the UK after an online consultation, Sildenafil is taken when needed, usually about one hour before sex, with effects lasting for up to 4 hours. Many men find that treatment helps them feel more confident about intimacy again.
Complete a short online consultation to check whether Sildenafil pills are suitable for you, and get back to feeling like yourself again.
The manufacturer of the product supplied may vary. Please read the patient information leaflet that is provided with the product. If you would like a specific brand please do contact our customer services team.
Product Information for Sildenafil tablets (25mg, 50mg, 100mg)
About Sildenafil
The Sildenafil film-coated tablet is the generic version of the well-known Viagra brand of ED tablets. This means they contain the same active ingredient (Sildenafil). They’re available in strengths of 25mg, 50mg and 100mg, and in quantities of 4, 8, 16, 32 or 64 tablets.
Sildenafil key features
Sildenafil is often known as an ‘on-demand’ treatment because it only needs to be taken around 1 hour before sex, rather than daily.
Oral tablet
Works in as little as 30 minutes
Lasts up to 4 hours
Read more about taking Sildenafil in the Directions for Use section and remember to always read the Patient Information Leaflet that comes with the medication.
How does Sildenafil work for Erectile Dysfunction?
Sildenafil belongs to a group of medicines called PDE5 inhibitors, which treat erectile dysfunction by increasing blood flow to the penis during sexual stimulation.
Normally, an enzyme called PDE5 breaks down the chemical signals that allow erections to happen. Sildenafil blocks this process so blood vessels stay relaxed for longer, helping you achieve and maintain an erection when sexually aroused.
Importantly, Sildenafil does not increase libido or cause automatic erections. It works only when you are sexually stimulated.
Am I eligible for Sildenafil tablets?
Sildenafil film-coated tablets are a prescription-only medication. You might be suitable if you meet the criteria below, however a doctor will complete a full clinical review of your completed online assessment before issuing a prescription.
Male (those assigned male at birth)
Aged 18 or over
There are several factors where Sildenafil may not be an appropriate treatment, including if:
You take nitrates for a heart condition. These are usually tablets or capsules called Isosorbide Mononitrate or Nicorandil (a medicine very similar to a nitrate) but can be called by other names
You use poppers
You have angina or have ever been given a spray that goes under your tongue to help chest pain
You have had a heart attack or stroke within the last six weeks
You have a condition called Peyronie’s or your penis has a bend when erect
You, or anyone in your family, has a history of eye disease, including retinitis pigmentosa or non-arteritic anterior ischaemic optic neuropathy (NAION)
You have liver or kidney problems
You have sickle-cell disease, multiple myeloma, or leukaemia
You have a stomach ulcer
You have low blood pressure
You have uncontrolled high blood pressure
Our expert team are on-hand to have a confidential and judgement-free chat about any concerns or finding the right treatment path. Call us on 01295 262925 or email help@oxfordop.co.uk.
Sildenafil tablets (25mg, 50mg, 100mg) reviews
How to use Sildenafil tablets (25mg, 50mg, 100mg)
Sildenafil film-coated tablets come in strengths of 25mg, 50mg and 100mg. They’re prescription-only and should always be taken as directed.
Make sure to thoroughly read the Patient Information Leaflet that comes with your medication.
How to take Sildenafil
Sildenafil is often known as an “on-demand” erectile dysfunction treatment because it’s taken before sex rather than every day. It is taken as a pill swallowed with water around one hour before sex. For best results, you should try to:
Take Sildenafil on an empty stomach if possible
Allow time for sexual stimulation
Avoid heavy meals immediately beforehand
Always follow the instructions provided by your prescriber and read the Patient Information Leaflet supplied with your medication.
When should I take Sildenafil?
Sildenafil pills are usually taken around 30 to 60 minutes before sex. Taking them ahead of time allows the medicine to start working so your body is better able to respond to sexual stimulation.
Some men notice they can get an erection firm enough for sex sooner than this. How quickly Sildenafil works can vary depending on factors such as recent meals, metabolism, dose strength, and general health. Taking it on an empty stomach may help it work more quickly.
If you don’t time it perfectly, don’t worry. The effects of Sildenafil typically last for up to 4 hours. You won’t have an erection for this entire time, but it does mean your body is better able to respond to sexual stimulation within that window.
What Sildenafil dosage should I start with?
Most men start with Sildenafil 50mg tablets, which work well for many people.
Depending on how well this dose works for you and whether side effects occur, it may be reduced to 25mg or increased to 100mg. This is the maximum amount of Sildenafil you should take daily. Exceeding this dose doesn’t improve effectiveness, but it does increase the risk of side effects.
The right dose depends on how your body responds and your general health, which is why treatment is always reviewed as part of your consultation.
How long does Sildenafil take to work?
You should take your dose of Sildenafil up to an hour before intercourse and it should start to work in around 30 minutes. It requires sexual stimulation to work.
How long does Sildenafil last?
The effects of Sildenafil typically last for 4 hours. This doesn’t mean that you’ll have a constant erection during that time. Instead, it offers a window in which it becomes easier to get an erection when you’re sexually stimulated.
How often should I take Sildenafil?
The recommended maximum dosing frequency is once daily. As the standard dose for most men is 50mg, it is recommended to only take 50mg in 24 hours. However some men may require a higher dose. In either case, you should not take more than 100mg in a 24-hour period.
Sildenafil is not licensed for daily use and is intended to be taken on an “as needed” basis. This means it should be taken 30 to 60 minutes before sexual intercourse, not every day. Taking Sildenafil daily is not recommended and may increase the likelihood of adverse effects.
If you’re considering a daily treatment, Tadalafil may be a good fit for you. Always talk to your prescriber before increasing your dose, frequency or switching treatments.
Side effects of Sildenafil tablets (25mg, 50mg, 100mg)
Below we’ve listed some of the ‘Common’ side effects of Sildenafil tablets. You should always read the Patient Information Leaflet that comes with your medication. A copy of this will also be in the medication packaging or box.
Common side effects (may affect up to 1 in 10 people)
Headaches
Flushing (red and/or warm skin on the upper body, often on the face)
Stuffy nose
Upset stomach
Nausea
Dizziness
The side effects listed below are more serious, and you should stop taking Sildenafil, and get medical help immediately.
An erection that will not go away (priapism). If you have an erection that lasts more than 4 hours, seek medical help immediately. Priapism can permanently damage your penis.
Sudden vision loss in one or both eyes. Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy (NAION). Stop taking Sildenafil and get medical help right away if you have sudden vision loss in one or both eyes.
Sudden hearing decrease or hearing loss. Some people may also have ringing in their ears (tinnitus) or dizziness. If you experience these symptoms, stop taking Sildenafil and contact a doctor right away.
If you would like to talk to our Healthcare Advisors about any concerns around side-effects please call us on 01295 262925 or email help@oxfordop.co.uk.
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Sildenafil is used to treat erectile dysfunction. It is taken shortly before sex to help men achieve and maintain a firm erection long enough to have sex. It does this by increasing blood flow to the penis during sexual stimulation.
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As part of your consultation, we will ask you to select your preferred treatment if you have one.
Generic Sildenafil suits most people who use it. The brand or packaging can sometimes change depending on which stock we get from our wholesaler.
Some people prefer to have the same brand with every order. In this case, you can order Sandoz Sildenafil or Teva Sildenafil and get the same product every time.
Sandoz Sildenafil is a popular choice because neat score lines across the tablets make them easy to break into halves or quarters.
Sildenafil is also available under the brand name Viagra, which is more costly.
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It does. Several clinical investigations showed that Sildenafil works well for treating ED. People who used the medication in these studies were better able to achieve and maintain erections that allowed successful intercourse.
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Sildenafil is an effective drug for Erectile Dysfunction (ED) and starts to work as quickly as 14 minutes in some men.
Sildenafil lasts for up to 4 hours after taking it. However, in some men, the effects could last up to 10 hours. Within 24 hours, the medication is at very low or undetectable levels in the body.
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No more than 100mg of Sildenafil should be taken daily. Taking more than 100mg doesn’t increase Sildenafil’s effectiveness, but it can lead to an increase and severity of side effects.
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There are several tablet alternatives to Sildenafil. They all produce the same result of helping to get or maintain an erection firm enough to enjoy sexual intercourse, but there are differences in when to take and how long they last for.
Tadalafil (Cialis)
Another oral pill, Cialis begins to function around 30 minutes after you take it and lasts for up to 36 hours. For “as needed” use, 10mg is the recommended starting dose. You can only take it once per day, just when necessary. Cialis may be taken with or without food.
There is also a once-daily variation. These 2.5mg or 5mg pills are taken every day at the same time, regardless of whether you have sex that day.
Vardenafil (Levitra)
Levitra takes up to an hour to start working. 10mg is often the initial dose. Again, this tablet can only be taken once per day, with or without food.
Avanafil (Spedra)
There are 50, 100, and 200mg tablets of Spedra available. You take it as needed, around 15 to 30 minutes before engaging in sexual activity. They may be taken with or without meals.
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It takes around 24 hours for Sildenafil to be cleared completely from the body, which is why you shouldn’t take more than one tablet per day. Its effects do not last for this entire time — the medicine is only effective for around 4 hours.
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Sildenafil is an ED treatment designed for biological males over 18 to get or maintain an erection firm enough to enjoy sexual intercourse. Sildenafil is not approved by the Medicines and Healthcare products Regulatory Agency (MHRA) for use by women.
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It’s not possible to completely prevent the side effects of Sildenafil. However, to reduce headaches, it’s best to make sure you drink lots of water, and limit your alcohol intake. To reduce flushing, try to cut down on coffee and keep the room cool or use a fan. And reducing GI side effects, avoid rich or spicy food, eat a light meal rather than a heavy or fatty meal. Equally, it’s always recommended to start on a lower dose to help your body adjust gradually.
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Sildenafil does not directly interact with alcohol, but drinking larger amounts can make erections more difficult to achieve and may increase side effects such as dizziness or headaches. For best results, keep alcohol intake to a minimum.
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Yes, Sildenafil can lower blood pressure. Sildenafil is a PDE5 inhibitor, which means it works by relaxing blood vessels to help blood flow to erectile tissue. This may mean it causes a mild, temporary drop in blood pressure.
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Yes, Sildenafil is considered a safe medicine when prescribed and taken appropriately. It is licensed in the UK for treating ED and is a well-established and widely prescribed medicine. However, it isn’t suitable for everyone, which is why clinical assessment is required before treatment is supplied.
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No, Sildenafil tablets are prescription-only medicines in the UK. However, you can safely buy Sildenafil online after completing a short medical consultation reviewed by a qualified clinician. Oxford Online Pharmacy offer this service for anyone who wants the ease of buying Sildenafil online.
Important - Before taking any medication, it is always important to read the Patient Information Leaflet (PIL)
Sildenafil tablets (25mg, 50mg, 100mg) - Patient Information Leaflet
NHS - Erectile Dysfunction
NHS - Sildenafil
- How blood affects erections: the science behind erectile dysfunction
- Why do ED medicines work for some people but not others?
- What is PDE5, and how do PDE5 inhibitors work?
- What we ask (and why) before we prescribe
- Can erectile dysfunction go away on its own?
- Comparing ED treatments, what do men try first?
- Can you have ED and still be healthy?
- Can a device really help with ED? What you need to know about Vertica
- Why ED medicines sometimes stop working
- How to take ED medication safely for the first time
Authored on February 10, 2026
Robert Bradshaw (Pharmacist) - MRPharms BSc(Hons) Pharmacy
Superintendent Pharmacist
GPhC Number: 2036118
Reviewed on February 10, 2026