Excellent 9.1/10
Fast and discreet delivery
Delivery method Cost
Free standard delivery
We dispatch orders from Monday to Friday. If placed before 4pm, your order will be dispatched the same day. Orders placed after 4pm will be sent the next working day.
Next Day Click & Collect
Collect your order from any Royal Mail post office. You will receive an email or SMS when your order is ready for collection. It will be available to collect for up to 18 days. Proof of Identification will be required.
Next Day Express Delivery
If placed before 4pm, your order will be delivered by 1pm on the next working day. Orders placed after 4pm will sent out the next day and delivered the day after.
+ £3.99
Saturday delivery
If placed before 4pm, your order will be delivered by 1pm on Saturday.
+ £7.99

You will choose your delivery option at the checkout. Delivery options
may vary depending on the pack size and dosage chosen.

Sildenafil is the active ingredient in Viagra. It is available as a lower-cost generic erectile dysfunction treatment.

To buy Sildenafil tablets online, you need a prescription. Our convenient service allows you to get a prescription and medication from DrEd.

To place an order, complete our short consultation and select your preferred treatment. Our online doctor will review your information and approve an appropriate treatment.

Sildenafil 50mg from £19
Sildenafil 100mg from £19

Prices include prescription and delivery.

Sildenafil is used to treat both erectile dysfunction and pulmonary arterial hypertension (PAH). It became well-known as the active ingredient in Viagra, a lower-cost alternative. In June 2013, Pfizer’s patent for Viagra expired, opening a market for generic sildenafil citrate. As a result, men now have a choice between branded Viagra and more affordable generic sildenafil tablets. Sildenafil is a prescription medication, meaning that it's only available on prescription and should be taken exactly as prescribed to be fully effective. You can order sildenafil tablets online from our team of doctors and have them delivered to the (UK) address of your choice.

What is the difference between sildenafil and Viagra?

The only difference between sildenafil and Viagra is the branding, and packaging, of the medication.

Viagra is the brand name for the generic medicine known as sildenafil. Sildenafil and Viagra are ‘medically equivalent’, meaning that they both work in the same way, and contain the same active ingredients.

What does sildenafil do?

Sildenafil is used to treat erectile dysfunction, when used alongside sexual stimulation. Sildenafil treats erectile dysfunction by relaxing the blood vessels in your penis, which allows the blood flow to increase. Good blood flow to the penis is necessary for a strong and healthy erection.

Sildenafil is not an aphrodisiac. It will not make you sexually stimulated or raise your libido on its own.

Can you drink alcohol and take sildenafil?

You can drink up to 2-3 units of alcohol, safely, while taking sildenafil. Many people find that alcohol helps them overcome their anxieties around sex.

However, too much alcohol can make your problems with erectile dysfunction worse. Drinking more than 2-3 units might have a negative effect on your sexual function.

How do you take sildenafil?

Always take your medication exactly as it was prescribed to you by your doctor.

As a rule, you should take your sildenafil tablets up to 1 hour before having sex. Swallow your sildenafil tablets whole, without chewing or crushing them. Take your sildenafil tablets with or without water, as desired.

Sildenafil works best on an empty stomach. It won’t be as effective immediately after eating a heavy, high-fat meal.

Sildenafil Dosage

Sildenafil is the active ingredient in Viagra. It causes the release of nitrous oxide (NO), a chemical that enlarges the blood vessels in the penis during sexual stimulation. This allows for the necessary inflow of blood needed to cause an erection.

Sildenafil Dosage 100mg, 50mg and 25mg

The Sildenafil dosage you need to take will depend on your age, gender, medical condition, your response to therapy and use of any interacting medication. 25, 50 and 100mg Sildenafil tablets are available. The recommended dose for most people is 50mg taken between 30 minutes and four hours prior to sexual activity. This dose can be increased to 100 or decreased to 25mg depending on adverse effects and efficacy. Ideally, it should be taken on an empty stomach. If you take Sildenafil after eating, it will take longer to kick in. Your tablet should be swallowed whole with a drink of water. Sildenafil should not be taken more than once in a day.

Drinking grapefruit juice while using this medication can be dangerous. It may increase the drug's concentration in your blood, causing more pronounced Sildenafil side effects.

The following patients should stick to 25mg Sildenafil tablets:

  • anyone over 65 years of age
  • with liver failure
  • with creatinine clearance <30ml/min
  • using potent cytochrome P450 inhibitors

Sildenafil Side Effects

When using this medication, you may experience one or more of the following, common Sildenafil side effects:

  • dizziness/ lightheadedness
  • headache
  • flushing
  • heartburn or indigestion
  • nosebleeds or nasal congestion
  • trouble sleeping
  • edema (swollen hands, ankles or feet)
  • visual disturbances (blurred vision/ increased sensitivity to light/ blue-green colour blindness)

If any Sildenafil side effects worsen over time, or are particularly uncomfortable, consult your doctor or pharmacist.
If you experience any of the following, serious side effects during sex and you have outstanding heart problems, stop taking Sildenafil and get medical help.

  • severe dizziness
  • fainting
  • chest/ jaw/ left arm pain
  • nausea

If you experience any of the following side effects, it indicates than an allergic reaction has occurred, (although rare, this is a serious problem and you should seek medical attention at once):

  • rash
  • itching/ swelling (particularly of the face, tongue and throat)
  • severe dizziness
  • trouble breathing

If you experience a sudden loss of hearing in one or both ears, or a ringing in your ears while using Sildenafil tablets, consult a doctor at once.
If you experience a sudden loss of eyesight in one or both eyes (NAION) stop taking the medication, and consult a healthcare professional at once. This is a very rare Sildenafil side effect, although your chances of experiencing it increases if you already suffer from any of the following:

  • heart disease
  • diabetes
  • high cholesterol
  • high blood pressure
  • existing eye problems
  • you are over 50
  • you are a smoker

Sildenafil Drug Interactions

Whether taking Sildenafil 100mg, 50mg or 25mg, you should keep a list of all the products you use (including prescription/ non-prescription and herbal medication) and share it with your doctor or pharmacist.
Do not start, stop or change your intake of Sildenafil tablets without first discussing it with your doctor. Sildenafil must not be taken with any form of nitrate medication as this combination can produce a severe drop in blood pressure that can cause dizziness, fainting, or even heart attack. Nitrate medications include the following:

Glyceryl trinitrate, isosorbide mononitrate and isosorbide dinitrate (used for angina or heart failure - if you experience chest pain after taking this medicine DO NOT use nitrates to treat it):

  • nicorandil
  • amyl nitrate 'poppers'
  • Some other products that may negatively interact with sildenafil are:
  • alpha blockers (doxazosin, prazosin, terazosin)
  • HIV drugs (ritonavir, saquinavir, delavirdine)
  • St John's Wort
  • cimetidine
  • anticonvulsants (carbamazepine, phenobarbital, phenytoin)
  • azole antifungals
  • macrolide antibiotics (erythromycin, rifamycins)

Precautions: Before Taking Sildenafil

You should not start taking Sildenafil tablets without first consulting your doctor or pharmacist. Inform them of your full medical history, paying particular attention to the following:

  • sickle cell disease;
  • high or low blood pressure;
  • dehydration;
  • priapism (painful erection problems);
  • eye problems (such as blurred or loss of vision in one or both eyes);
  • heart problems (arrythmia, angina, heart attack, aortic stenosis etc);
  • kidney disease;
  • liver disease;
  • fluid in the lungs;
  • problems with the shape of the penis (angulation, fibrosis/scarring);
  • stroke in the past 6 months.

A common Sildenafil side effect is loss of vision or bouts of dizziness, therefore do not drive, operate machinery or engage in any task that requires intense concentration or alertness until you are confident that this side effect doesn't apply to you. Limit alcohol intake when using Sildenafil tablets.

If you are a woman using Sildenafil (Revatio) you should take care not to fall pregnant. During pregnancy, Sildenafil should only be taken when there is a clear need and it has been prescribed by a doctor. Discuss the risks and benefits with your doctor. It is not known whether this medication passes into breast milk, so consult your doctor before breast feeding.

The elderly should take this medication with caution as its effects can be more pronounced. If your erection lasts longer than four hours, consult a doctor at once as this can cause permanent damage to your penis.




If you have a question about this service, please email [email protected] with the question, and one of our doctors will get back to you within 24 hours.

This service is also available in the following countries:

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Our fast, convenient service is extremely straightforward
and you don't need to visit a doctor to use it.

Choose your medication

You'll complete a short online health assessment and choose the medication you need. If you're unsure, our in-house GPs can also recommend the best treatment for you.

Our in-house GP prescribes your medication

Our doctors will review your order, issue your prescription and pass it straight to a pharmacist to be dispensed.

Delivered to your door or collect from store

Free First Class delivery is included and next day delivery starts at just £3.99. OR you can collect from any Royal Mail Local Collect® at your convenience.

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Complete Confidentiality

We take precautions that other online providers don't,
so you’re given a convenient and discreet service.

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FREE Fast Delivery

Orders placed before 4pm will be dispatched the same day.

Next Day Click & Collect

Available to Collect: Thursday 25 Feb 2016 after 11am
Get an SMS/email to collect from your preferred Royal Mail location

Standard Delivery

Estimated Delivery: Saturday 27 Feb 2016 - Tuesday 01 Mar 2016

Next Day Express

Estimated Delivery: Friday 26 Feb 2016 by 1pm

Discreet Packaging

All of your medication will be delivered in plain, unlabeled
packaging. A signature will be required but it does not
have to be the patient.

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1,000,000 Customers Treated

DrEd is a brand you can trust. We've treated 1,000,000 patients
since 2011, and are certified by the CQC and MHRA.

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