Click Health

Sildenafil (Generic Viagra)

  • Genuine UK treatment
  • MHRA approved
  • Same day delivery available

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Sildenafil’s active ingredient (Sildenafil Citrate) belongs to a class of drugs called phosphodiesterase inhibitors. This prevents the breakdown of a natural molecule produced by your body which stimulates an erection when you get aroused. It does so by increasing blood flow to the penis to help men get and maintain an erect penis.
It is reported that at least two-thirds of men have improved erections after taking it. If you have eaten a large meal or drank more than 1-2 units of alcohol, you may find Sildenafil to be less effective. If Sildenafil does not work for you, it may be because:
  • you have not waited long enough after taking it before trying to have sex
  • you have waited too long after taking it to have sex
  • the dose is not high enough
  • you're not sexually aroused enough
The recommended starting dose is 50mg tablet once a day. To get the most benefit, swallow the medication whole with water on an empty stomach one hour before sexual activity as food will slow down the absorption of Sildenafil, delaying its effect. However, eating an hour after taking the pill will not affect its activity.

Heavy alcohol consumption should also be avoided as it causes a drop in blood pressure, which makes it even more difficult to get an erection. You should be able to get an erection at any time between 1 to 4 hours after taking Sildenafil.

Do not combine Sildenafil with other erectile dysfunction medicine and never take more than one tablet in 24 hours (unless advised to do so).
Like any medicine that is taken, Sildenafil can potentially cause side effects or have no side effects at all. These include headache, nausea, hot flushes and dizziness, nasal congestion, indigestion, palpitations, and blurred vision.

However, many men report no or otherwise very mild side effects.
Which ED treatment works for you best depends on the individual and their sexual activity. Here is a few tips to help you make a selection:

Sildenafil (or Viagra) typically works within an hour of taking and last up to 4-5 hours. Sildenafil is the active ingredient of Viagra however, it is a generic version of the brand available at a cheaper price with the same actions. You may start taking sildenafil (or Viagra) at the typical dose of 50mg. This can then be decreased to 25mg or increased to 100mg depending on how you react to the 50mg dose. 

Tadalafil is also common prescribed erectile dysfunction treatment. It is the generic version of Cialis and so considerably cheaper. Tadalafil is sometimes favoured as it lasts up to 36 hours after taking hence why we sometimes refer to it as the The Weekend Pill. Tadalafil also works faster being effective within 30 minutes. Some prefer using Tadalafil rather than Sildenafil as it is not effected by food. The standard prescribed dose for Tadalafil is 10mg which can be increased to 20mg if not effective. If you typically have sex more than 2x a week or are spontaneous with your sexual activity, you may prefer to try the 2.5-5mg dosing taken daily. If you are the type to have no schedule, then this is a perfect fit.

Vardenafil is another choice of ED treatment. It is the generic version of Levitra and so is considerably cheaper but offering the same mechanism of action. Vardenafil works within 30-60 minutes of taking and last for 5 hours. Similarly to Sildenadil, it works best on an empty stomach. The standard dose of 10mg is prescribed however, a lower or higher dose may be prescribed depending on several factors.

Please note some health condiitons may result in a lower dose being more safe to take hence why it is vital to state your full medical history so our prescribers can make an informed decision.
Sildenafil is used to treat erectile dysfunction and will not directly help with premature ejaculation. An alternative medication that has been proven to help with premature ejaculation is Dapoxetine (Priligy) which you can purchase from our Click Doctor Men's Clinic.
Some medicines are not suitable for people with certain conditions or on particular medicines. It is very important you declare your full medical history to our Click Doctors via our online consultations so that a proper judgement can be made on its safety.

Sildenafil is not suitable:
  • If you are allergic to its active ingredient or any other of its ingredients.
  • If you are on nitrates or nitric oxide donors
  • If you have loss of vision in one eye due to non-arteritic anterior ischaemic optic neuropathy
  • If you have any heart problems or suffered from a stroke within the last 6 months
  • If you have been advised against having sex e.g. due to heart problems
  • If you are using any other products or taking any other medicines to treat erectile dysfunction.

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 prevent you from getting the maximum benefit from this treatment.

You should not drink grapefruit juice with Sildenafil since it can increase the amount of Sildenafil in your bloodstream and make side effects more likely.

For full information on how to take, side effects and precautions, it is important that you carefully read the patient information leaflet.

Note: Our Click Doctors recommend generic Sildenafil. It contains the exact same active ingredient as the branded Viagra (Sildenafil Citrate) at a much lower price!
Superintendent Pharmacist: Isra Al-Hadad
GPhC Reg No: 2076850