Viagra (branded Sildenafil)

Side effects are uncommon, but can include nausea, vomiting, back pain, diarrhoea and an allergic rash. Some men also experience facial flushing, headaches, light headedness, nasal congestion, indigestion, palpitations (racing heartbeat), and blurred vision.

For full information on side effects and correct use, see the patient information leaflet.

The standard dose is 50mg. Depending on your age, height and weight, the cause and the severity of your ED, you may be prescribed a lower dose of 25mg, or a higher one of 100mg. Dosage does not affect how quickly or for how long the treatment works.

Higher doses come with an increased chance of developing side effects.

If you are taking alpha-blockers (such as doxazosin or tamsulosin), you should wait at least 6 hours between taking those and taking Viagra.

You will be unsuitable for Viagra if you are taking nicorandil or nitrates, such as GTN spray or isosorbide mononitrate tablets to treat angina.

It is important that you let us know which prescription, over-the-counter medicines and recreational drugs you are taking so that we can prescribe Viagra safely.

Some men find counselling helpful as a means of exploring and treating psychological causes for ED.

If Viagra does not work for you, contact us via your Patient Record so that we can discuss your treatment options. View all our ED treatments.

To reorder Viagra, go to your Patient Record and select ‘reorder’. You will be required to fill in the online questionnaire each time you reorder.