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Sildenafil tablets
Sildenafil is an oral tablet (brand name Viagra) used for erectile dysfunction.
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What is Sildenafil?

Sildenafil is a treatment for erectile dysfunction (ED) known as a PDE-5 inhibitor. It's the non-branded version of Viagra. Both Sildenafil and Viagra contain the active ingredient sildenafil citrate and work to treat ED in exactly the same way, but Sildenafil tends to be cheaper as it doesn't have the Viagra branding. Our clinicians can prescribe both Sildenafil and Viagra, as well as other ED medicines, so whatever treatment is right for you, we can help.

Find out more about our ED treatment service.

What is Sildenafil used for?

Sildenafil is primarily used for the treatment of erectile dysfunction in men.

It can also be used in the management of finger or toe ulcers and lung conditions.

How does Sildenafil work?

Sildenafil is a PDE-5 inhibitor (phosphodiesterase type 5 inhibitor), which means it blocks the effects of the PDE enzyme, relaxing the blood vessels in the penis and helping to increase blood flow. This can help men to achieve and maintain an erection hard enough for sex. Sildenafil tablets are effective in around 60-70% of men when taken as prescribed.

In order for Sildenafil to work, you need to be sexually aroused. You won't get a spontaneous erection just from taking it.

Erectile dysfunction is not the same as premature ejaculation. It's unlikely that Sildenafil will increase the amount of time you can have sex. It works by supporting your body to function the way it usually would when you feel aroused.

In other words, Sildenafil can help you to experience sexual stimulation and orgasm the same way you would naturally. It won't make you last longer in bed or have more orgasms. If you're experiencing premature ejaculation, we can help.

How to take Sildenafil tablets

Take one Sildenafil pill one hour before sexual activity on an empty stomach. Avoid alcohol and take the tablet at least an hour before food or at least two hours after eating.

Grapefruit can increase the risk of experiencing side effects. We recommend you avoid eating grapefruit or drinking grapefruit juice on the days you take this medicine.

Take this medicine only as needed. Never take more than one pill within 24 hours and do not combine it with other ED medicines.

Feel free to contact our clinical team through your online patient record if you have any other questions about how to take Sildenafil.

Sildenafil dosage

Sildenafil comes in three different dosages: 25mg, 50mg and 100mg. One of our clinicians can help you decide on an appropriate starting dose.

Sildenafil 50mg is the most usual starting dosage. We may recommend 25mg if you've previously tried 50mg but experienced some side effects. Sildenafil 100mg may be an option for you if you've previously tried 50mg but didn't get the results you were hoping for.

Is Sildenafil effective?

In patients with erectile dysfunction, 60%-70% of patients will see a positive outcome from the use of PDE5 inhibitor medicines like Sildenafil.

What are the main side effects of Sildenafil?

Like any medicine, Sildenafil comes with a risk of possible side effects. Make sure to read the treatment plan we send and the Patient Information Leaflet for full details on possible side effects before taking Sildenafil.

Common side effects include facial flushing, headache, lightheadedness, stuffy nose, indigestion, a pounding heartbeat, and, in some men, blurred vision and blue halos appear around bright lights.

Chest pain is an uncommon, but potentially serious, side effect. If you experience this during or after sexual intercourse, get in a semi-sitting position and try to relax. If the pain continues beyond 15 minutes then call the emergency services.

Prolonged and painful erections are a rare side effect. Should this happen and last for more than four hours then you should contact a doctor immediately.

If you're worried about any side effects you experience, please contact us through your online patient record.

What else should I know about Sildenafil?

If you're also on a nitrate drug for heart problems or if you've had a heart attack in the last six months, Sildenafil may not be suitable for you. Sildenafil should not be used in patients with certain hereditary eye conditions and it can interact with some medicines to cause serious heart issues.

It's really important you provide an accurate and thorough medical history during your online consultation so our clinical team can prescribe treatment that's appropriate for you.

What are alternative ED treatments?

We have a range of ED treatments we can prescribe. If you need help choosing an ED treatment that's right for you, we can help. For an erectile dysfunction pill that can support you in getting an erection for up to 36 hours, we'd recommend trying Tadalafil.

Find out more about ED treatments we offer.

What are the non-drug alternatives to Sildenafil?

If you're suffering with erectile dysfunction, there are a few lifestyle changes you can make to try and help improve your symptoms:

If you feel that stress and/or anxiety could be contributing factors, speak to your GP about counselling or behavioural support therapy.

You can also find more information and advice on erectile dysfunction on our Lifestyle Medicine pages.

Finally, the use of vacuum erection or implant devices can be an option for some men. Please speak to your GP for more information on these alternative treatment options.

Can I become psychologically dependent on Sildenafil?

When used appropriately at the advised dose, there is no evidence regarding developing dependence or tolerance with long-term use of Sildenafil.

It's important though that you only use ED medicines as instructed by your healthcare provider. If used incorrectly there could be a possibility of negative side effects and psychological dependence.

Is Sildenafil physically addictive?

You don't need to worry about physical addiction or suffering with withdrawal effects when you stop taking Sildenafil. There currently isn't any evidence to suggest ED medicines are physically addictive.

Can I buy Sildenafil online?

You need a prescription to buy Sildenafil. You can go to your GP for this or get Sildenafil online by simply filling out our quick consultation for fast, discreet service.

You don't need to make an appointment or talk to anyone directly. You can get the advice and treatment you need without any awkwardness or embarrassment. And we know how important privacy and discretion is when it comes to sexual health.

Find out more about our ED treatment service.

We also offer Sildenafil on our Subscribe and Save service. So long as nothing changes with your medical condition, you can get your repeat prescription automatically for up to 12 months on Subscribe and Save without needing to do a thing. And you'll save at least 15% each time.

What is ED?

Erectile dysfunction (ED) is a term used to describe struggling to get and/or maintain an erection. You might hear it referred to as impotence. It's usually due to a combination of reduced blood flow to the penis and associated performance anxiety. It can affect anyone of any age group and is increasingly common in younger men.

What causes ED?

ED can be a symptom of other health issues and is often experienced by people who have underlying health problems such as heart disease, type 2 diabetes, high blood pressure, high cholesterol or depression. Smokers are at higher risk than non-smokers of experiencing erectile dysfunction. Reduced flexibility and blood flow in the arteries is the main underlying physical factor. Men who drink large amounts of alcohol are also at increased risk of erectile dysfunction.

Find out more about ED.

How long does Sildenafil last?

The effects of Sildenafil can last for up to five hours. It may not work the first time. You may need to try Sildenafil on up to four separate occasions to find out whether it's effective for you.

If you're looking for something that lasts longer, why not try Tadalafil? You only need to take Tadalafil around 30 minutes before you anticipate having sex and its effects can last up to 36 hours. This means you should be more likely to get an erection when sexually stimulated during that period of time.

What is the difference between Sildenafil and Viagra?

There is no difference between Sildenafil and Viagra, other than the branding. Both treatments include the same active ingredient, sildenafil citrate, and work to treat ED in the same way.

Because of the branding, Viagra tends to be more expensive, whereas Sildenafil can offer a cheaper alternative. We also offer Sildenafil on our Subscribe and Save service. With Subscribe and Save, so long as your medical conditions don't change, you can get your repeat prescription automatically for up to 12 months without needing to do a thing, and save at least 15% each time.

Find out more about our ED treatment service options.

Can women take Sildenafil?

Sildenafil is an erectile dysfunction treatment intended for use by men who need help getting an erection. It has no proven benefits for women and could potentially pose health risks. It's illegal for women to buy Sildenafil in the UK.


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