How should I take this medicine?

Sildenafil should be taken one hour before sex on an empty stomach. If you take this medicine with food, it may take a little longer to work.

How long will the effects of this medicine last?

Sildenafil can remain effective for up to 4 hours

What is the difference between Viagra and Sildenafil?

The active ingredient in Viagra is Sildenafil. Viagra is a branded medication, whereas Sildenafil is a generic medication. They both work in exactly the same ways, except that the generic Sildenafil offers a cheaper alternative for the same effect. They are both equally effective as each other. Click here for more information on branded and generic medicines.

I am taking medicine for erectile dysfunction the first time and I am unsure which should choose - Viagra, Cialis or Levitra?

If you are unsure which medicine to choose, we suggest you choose Viagra (brand) or Sildenafil (generic). This is because if you do experience any side effects it is likely that the side effects experienced with Viagra or Sildenafil will last for less time because it remains effective for the shortest time in comparison with Cialis and Levitra.

The most common side effect is headache. Less commonly you may also experience flushing, indigestion, nasal congestion, dizziness, nausea, hot flushes and visual disturbances. These common side effects do not usually last more than 3-4 hours after taking the medicine.

If after taking this medicine you experience an erection lasting for more than 4 hours you should seek medical advice from a doctor urgently.

Please click here to view a patient information leaflet on Sildenafil (Generic Viagra).

An alternative to Sildenafil or Viagra is Cialis or Levitra. If you are unsure which is best for you email us at freeadvice@myonlinedoctors.co.uk for more information.