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Start a discreet online consultation with our doctors to find out if sildenafil is the right treatment for your erectile dysfunction.

  • One of the most commonly used erecticle dysfunction treatments
  • Starts to work in 20 to 60 minutes
  • Increases blood flow to the penis

*Please note images are for illustration purposes and the packaging you receive may differ

Strength i

  • 25mg 25mg
  • 50mg 50mg
  • 100mg 100mg

Generic or branded i

  • Sildenafil (Generic Sildenafil)

£23.00 (£5.75 per tablet)

In Stock

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Our Doctor says...

Sildenafil is the generic version of Viagra. This means that it contains the same ingredient as Viagra but is made by a different manufacturer. It is used in the same way as Viagra and has the same benefits as the branded version.

Dr. Alex Phelan Pharmacy2U Online Doctor

More information about Sildenafil

How to take Sildenafil

Sildenafil is a prescription only medication. Sildenafil is taken as a tablet, when needed. It should be taken 30 minutes to an hour before sex. No more than 100mg should be taken in a day.


The usual starting dose is 50mg, with the option to reduce to 25mg or increase to 100mg, depending on effectiveness and side effects experienced.


Sildenafil works by relaxing the blood vessels to the penis, allowing better blood flow when sexually aroused. Sildenafil is effective for most men with erectile dysfunction.

Side Effects

As with all medicines, sildenafil can cause side effects, but not everyone experiences them. If taken at the recommended dosage, the side effects of this drug are usually mild and will pass with time. The most common side effects are headaches and facial flushing. Less common effects include indigestion, dizziness, stuffy nose and visual effects (a blue coloured tinge to vision and increased brightness of light or blurring). If you experience any troublesome side effects, or a prolonged and painful erection, stop using the medicine and seek medical assistance immediately.

Nitrates and Alpha Blockers

You should not take sildenafil with medications known as nitrates. Both of these cause the muscles that control the size of blood vessels to relax, which could cause a drastic drop in blood pressure. Nitrates are found in drugs used to treat chest pain and angina, and in the recreational drug ?poppers?. It is advised not to take any medicines called 'alpha blockers' with sildenafil without speaking to a doctor first. Always consult your doctor before combining any medications and make sure you tell our online doctors about any other medicines you take. Always read the leaflet carefully before taking sildenafil.

How long does it take to work?

Sildenafil should be taken at least 30 to 60 minutes before you wish to have sex. You will still need sexual stimulation to achieve an erection when you have taken it.

How long does it last?

Sildenafil remains effective for around four to five hours after taking.

How does it work?

An erection occurs when the penis fills with blood. The blood vessels that bring blood to the penis dilate, increasing the blood supply. Blood accumulates in the penis, causing an erection. Sildenafil allows better blood flow to the penis by relaxing the blood vessels.

Who should take sildenafil?

Sildenafil can be taken by men over 18 with erectile dysfunction.

Who should not take sildenafil?

Do not take sildenafil if you are allergic to it or any of the other ingredients of the tablet. Sildenafil is not suitable for use by those with serious heart or liver problems, those who have had recently had a stroke or a heart attack, those with low blood pressure, or those with some rare inherited eye diseases. Sildenafil also is not suitable for women, or men under 18.

How do I take sildenafil?

Sildenafil should be swallowed with a glass of water. It's best to take sildenafil on an empty stomach.

Can I take sildenafil with other medication?

You must let your doctor know if you are taking any other medications, whether prescribed or purchased over the counter, especially if you take nitrates for chest pain, riociguat for pulmonary hypertension or any recreational drugs called 'poppers'. Some herbal remedies and supplements may interfere with sildenafil. It is also important to let us know if you use, or have used, other erectile dysfunction medications.

"If sildenafil does not work for you, there are alternative medications available. You could try Cialis (tadalafil), Levitra (vardenafil) or Spedra (avanafil). Cialis is effective for up to 36 hours, and can be taken as a once daily tablet (2.5mg or 5mg), or just when required (10mg or 20mg). Levitra comes in strengths of 5mg, 10mg and 20mg. It has been shown to be effective in a wide range of age groups and for men with conditions such as high blood pressure, diabetes, depression and high cholesterol. Spedra comes in strengths of 50mg, 100mg and 200mg, and has been shown to work well for men with erectile dysfunction caused by type 1 and type 2 diabetes. Spedra can work within 15-30 minutes of taking the dose - this is faster than Viagra, Levitra or Cialis."


Can I take sildenafil and drink alcohol?

Most erectile dysfunction medications lower your blood pressure, as does alcohol. Combining the two could cause you to experience light-headedness, dizziness, fainting or heart palpitations. Alcohol could also have an impact on the effectiveness of the drug.

Which medication is best?

There are several options for erectile dysfunction medicines. One drug may be more suited to you than another. Begin an online consultation with our doctors, who will be available to advise you.

What if Sildenafil doesn?t work for me?

Sildenafil may not work for everyone. There are other erectile dysfunction medications available through our service. Consult our doctors about the best option for you.

Can young men get ED?

Older men are more likely to experience erectile dysfunction, but younger men can be affected too. Causes can be physical or psychological.