They work by opening the blood vessels in the penis, the increased blood flow helps maintain an erection.

Sildenafil is the drug contained in several products, including Viagra Connect and Viagra. Sildenafil, or as some people know it Generic Viagra has been available since 2013, helping men get great value, low-cost treatment for their ED.

Sildenafil is a medicine that belongs to a group of drugs known as phosphodiesterase type 5 inhibitors, or PDE5 for short. These medicines, which includes Sildenafil help men who suffer erectile dysfunction get and maintain an erection suitable for sex. They work by opening the blood vessels in the penis, the increased blood flow helps maintain an erection.

Sildenafil should be used when sex is anticipated. It should ideally be taken 30-60 minutes before sex on an empty stomach or after a light meal.

Sildenafil 50 mg tablets are generally where most men start. If you get too many side effects try 25mg or If Sildenafil 50mg tablets are ineffective then try 100mg next time.

Active ingredient: Sildenafil citrate in 25mg, 50mg or 100mg doses.

Other ingredients include:Lactose monohydrate, hypromellose 15cP, titanium dioxide (E171), triacetin

The ingredients provided on this page refer to a generic version of the product. Ingredient lists may vary slightly depending on the manufacturer of the specific treatment you receive. However, the active ingredient and its therapeutic effect will remain the same across all manufacturers.

Very common side effects (may affect more than 1 in 10 people) include:

• Headache

Usually mild and often improves over time. You may find it helpful to:

• Drink plenty of water
• Take paracetamol
• Speak to your prescriber about lowering your dose or trying an alternative PDE-5 inhibitor if headaches continue

Common side effects (may affect up to 1 in 10 people) include:

• Nausea
• Facial flushing
• Hot flushes (a sudden feeling of heat in your upper body)
• Indigestion
• Stuffy nose
• Dizziness
• Visual disturbance (including a colour tinge to your vision or blurred vision)

NB: In regards to visual disturbances, some men may notice blurred vision or a blue or coloured tinge to their vision when taking sildenafil. Although this can sound worrying, it is a recognised side effect and is usually temporary.

You should consult with your doctor or pharmacist before taking sIldenafil if you have:

• Sickle cell anaemia
• Leukaemia
• Multiple myeloma
• A deformity of the penis or Peyronie’s Disease
• An existing heart condition
• High blood pressure (hypertension)
• Chest pains
• Kidney or liver conditions

Sildenafil is for use by men over the age of 18 with ED. You should not use this treatment if you:

• Are a woman
• Are under the age of 18
• Do not have ED

Sildenafil can interfere with some medications, most commonly those used to treat chest pain (nitrates). As such, you should not take these in conjunction as they may lead to a dangerous fall in blood pressure.

In the event of a medical emergency, you should tell your doctor or pharmacist that you have taken sildenafil, the dosage and when it was taken.

For a full list of warnings and side effects, please see the Patient Information Leaflet.