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    Potential side effects of Sildenafil

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      How Sildenafil works

      Sildenafil is an erectile dysfunction treatment that contains the same active ingredient as Viagra - sildenafil citrate - and functions in a very similar fashion, by increasing the flow of blood to the penis during sexual arousal. In some cases, side effects from Sildenafil can occur in a small number of men.

      Side effects of Sildenafil

      Very common (occur in 1 in 10 people)

      • Headache/nausea

      Common (affect between 1 in 10 and 1 in 100 people)

      • Stuffy nose
      • Dizziness
      • Facial skin flushes
      • Indigestion
      • Difficulty with vision, including blurred sight, light sensitivity, colour tinge

      Uncommon (affect between 1 in 100 and 1 in 1000 people)

      • Bladder pain
      • Chest and muscular pain
      • Dehydration
      • Pain or discomfort in your eyes - may include blurred or double vision, watery eyes, bloodshot eyes, increased sensitivity, bleeding in the eye
      • Vertigo
      • Heart palpitations and an increased heart beat
      • Blood in your urine or semen (or bleeding from your urethra)
      • A numbing sensation or hypersensitivity to pain or touch
      • Feeling sleepy
      • Tinnitus or hearing noises in your ear
      • Vomiting
      • Skin rashes

      Rare (affect between 1 in 1000 and 1 in 10,000 people)

      • Stroke or other heart related medical conditions
      • Lightheadedness leading to passing out or fainting
      • Nosebleeds
      • Problems hearing - either complete or sudden loss
      • Increased or decreased blood pressure

      Frequency unknown but very rare

      • Prolonged erection, or persistent painful erection of the penis (priapism)
      • Seizures or other epileptic reactions
      • Extreme chest pain/pounding heart
      • Sudden death due to heart attack
      • Extensive blistering of the skin (Stevens-Johnson syndrome)
      • Severe flaking of the surface layer of the skin (toxic epidermal necrolysis)
      • Unstable angina/irregular heart beats (arrhythmias)
      • Mini-stroke (transient ischaemic attack) or loss of blood supply to the brain

      How to decrease the risk of Sildenafil side effects

      • Avoid alcohol - Alcohol may not only increase your exposure to side effects, but it can make Sildenafil less effective. It is advised that you do not drink more than one or two units of alcohol when taking Sildenafil, to minimise the chance of being exposed to side effects.
      • Avoid recreational drugs - Recreational drugs, particularly ‘Room Odourisers’ and ‘Poppers’, can cause a sudden drop in blood pressure which could be fatal. If you have any further queries, contact your doctor.
      • Take a lower dose - Sildenafil can be taken in doses of 50mg, 100mg and 200mg. While it may require some trial and error, taking a smaller dose can decrease the risk of side effects, while still remaining an effective ED treatment.
      • Potentially take with food - Sildenafil is most effective when taken on an empty stomach. But, if taken with food- while the absorption time might be longer- it could reduce the impact of side effects.
      • Check prescription medicines interactions with Sildenafil - Some prescription medicines contain drugs which can interact negatively with Sildenafil, thereby increasing your exposure to side effects. If in doubt, consult your doctor about which medicines are safe to take alongside Sildenafil.


      As Sildenafil shares the same active ingredient as Viagra, men feel confident in using this cheaper brand. The side effects are similar, and the likelihood of developing them is no greater than with Viagra. If you want to discuss the differences between Sildenafil and Viagra further, you can consult a medical professional.

      Order Sildenafil online here >

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