Do not take more than one dose of sildenafil in a 24-hour period.
Sildenafil will only work if you are sexually aroused, so ensure you still engage in foreplay.
Do not drink large amounts of alcohol before you plan to take sildenafil. Drinking too much alcohol can reduce your ability to get an erection and this may prevent you from getting the maximum benefit from the tablets.
It is recommended that you do not drink grapefruit juice with sildenafil. This is because grapefruit juice can increase the amount of sildenafil in your bloodstream and this makes side-effects more likely.
If you feel the tablets are too strong for you, discuss this with the clinician as your dose may need to be reduced. Alternatively, if you do not get an erection after taking sildenafil, or if it does not last long enough for you to have sex, you should discuss this with your clinician - do not take more tablets than you have been told to.
You should not take sildenafil if you are using any other products or taking any other medicines that treat erectile dysfunction.
If you’ve had an erection lasting longer than 4 hours, it’s time to seek urgent help. Go to your local A&E immediately.