Take one tablet of Sildenafil about one hour before sex. For optimum performance, take on an empty stomach. The effects of Sildenafil can last between 4-6 hours.

Never take more than a 100mg tablet within 24 hours

Sildenafil should not be taken with more than one or two units of alcohol, as it may not be effective.

Sildenafil works by increasing blood flow into the erectile tissue of the penis. Sildenafil does not have an impact on libido, only your ability to get and maintain an erection when sexual aroused.

Most men will notice a firmer and longer-lasting erection. If  the treatment does not work, ask our doctors whether it would be appropriate to increase the dose. Alternatively, they may recommend another treatment.

If Sildenafil doesn’t work for you first time round, it could nevertheless be more effective next time. Doctors often advise trying all erectile dysfunction medicines eight times before giving up.

While side effects are uncommon, they can include nausea, vomiting and diarrhoea. Sildenafil can also cause nasal congestion, headaches, facial flushing, slight vertigo, a pounding heartbeat and blurred vision.

Sildenafil can not be prescribed by our doctor if you are taking nicorandil or nitrate based medication, such as GTN spray or isosorbide mononitrate tablets for angina.

If you are taking alpha-blocking medicines, such as tamsulosin or trazodone, you are advised to leave at least six hours between taking your alpha-blocker and Sildenafil.