Sildenafil 25mg, 50mg or 100mg

Buy Sildenafil for Erectile Dysfunction

Sildenafil is a treatment for men with erectile dysfunction (ED), sometimes known as impotence. This is when a man cannot get, or keep a hard, erect penis suitable for sexual activity. It is important to note that Sildenafil will only help you to get an erection if you are sexually stimulated.

All our products are genuine UK medicines and are dispensed by our partner pharmacy based in the UK.

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  • Sildenafil is the generic version of Viagra
  • Available in 25mg, 50mg or 100mg strengths
  • Can be purchased alone or as part of an ED trial pack
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Sildenafil contains the active substance sildenafil which belongs to a group of medicines called phosphodiesterase type 5 (PDE 5) inhibitors. It works by helping to relax the blood vessels in your penis, allowing blood to flow into your penis when you get sexually excited. In most men Sildenafil works within an hour and effects last for about four hours - this doesn't mean the erection lasts for four hours, rather that an erection can be produced for up to four hours after taking a tablet.


Do not take Sildenafil:

  • if you are allergic (hypersensitive) to sildenafil or any of the other ingredients listed in the patient information leaflet
  • if you are taking medicines called nitrates (often given for relief of angina pectoris (or chest pain) - the combination may lead to a dangerous fall in your blood pressure
  • if you are using any of the medicines known as nitric oxide donors such as amyl nitrite (poppers), as the combination may also lead to a dangerous fall in your blood pressure
  • if you are taking riociguat - a drug used to treat pulmonary arterial hypertension (i.e. high blood pressure in the lungs) and chronic thromboembolic pulmonary hypertension (i.e. high blood pressure in the lungs secondary to blood clots)
  • if you have a severe heart or liver problem
  • if you have recently had a stroke or a heart attack, or if you have low blood pressure
  • if you have certain rare inherited eye diseases (such as retinitis pigmentosa)
  • if you have ever had loss of vision due to non-arteritic anterior ischaemic optic neuropathy (NAION)
Pregnancy and Breastfeeding

Sildenafil is not indicated for use by women

Important Interactions

Do not take Sildenafil with other medicines unless your doctor tells you that you can. You must tell your doctor if you are taking, have recently taken or might take other medicines, in particular:

  • medicines used to treat chest pain - in the event of a medical emergency, you should tell your doctor, pharmacist or nurse that you have taken Sildenafil and when you did
  • medicines called nitrates - the combination of these medicines may lead to a dangerous fall in your blood pressure
  • medicines known as nitric oxide donors such as amyl nitrite (“poppers”) - the combination may also lead to a dangerous fall in your blood pressure
  • riociguat
  • protease inhibitors, such as for the treatment of HIV
Side Effects
  • headache
  • nausea
  • facial flushing
  • hot flush
  • indigestion
  • colour tinge to vision
  • blurred vision
  • visual disturbance
  • stuffy nose
  • dizziness
Please Note

All medication can cause side effects. We have only listed a few to be aware of. Details of all side effects, including rare side effects to be aware of, are listed in the patient information leaflet (PIL). When completing your medical questionnaire, it is very important that you answer the questions truthfully. This is to ensure your doctor has a full picture of your medical history before prescribing. List all medicines you are already taking, including non-prescription and herbal medicines.


Viagra is also available and is the branded form of Sildenafil. Other ED medications include Cialis, Levitra and Spedra. Alternative treatments to ED medication include treating underlying physical or psychological causes, undergoing lifestyle changes, vacuum devices and surgical intervention.

Looking after your medicine

Do not take medicines after the expiry date stamped on the pack. Keep all medicines out of the reach and sight of children.

Medicines are only intended to be used by the person they are prescribed for. Do not give your prescribed medicine to anybody else, even if they have the same symptoms as you. Medicines can be harmful if used by anybody other than the person they have been prescribed for.

References Sildenafil 25mg, 50mg or 100mg Patient Information Leaflet
British National Formulary: sildenafil

The dose and quantity you can purchase will be set by your doctor. For first time users it is better to start with the lower dose and then increase the dose if necessary after discussion with your doctor. You should not change the dose of your medicine unless you are told to do so by your doctor. If you feel that the medicine is making you unwell or you do not think it is working, message your doctor from your patient medical record for help and advice.

Last reviewed & updated  21/03/2020   Authored  16/09/2009

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