Sildenafil dosage guide
Reviewed by Dr Bhavini Shah
Sildenafil is a popular erectile dysfunction (ED) tablet, taken by men who find it hard to get an erection on their own. It is the generic version of Viagra, which means it contains the same active ingredient (sildenafil citrate) and works in the same way.
Sildenafil is available in three different dosages: 25mg, 50mg and 100mg. If you are considering taking Sildenafil, but you aren’t sure which dosage is right for you, read on.
Getting treatment for erectile dysfunction
If you are having trouble getting and keeping erections, it’s important to speak to a doctor. Erectile dysfunction can be a sign of a serious health issue.
Dr Neel Patel explains that “if you keep experiencing ED and feel it is affecting your self-image or sex life, it may be a good idea to seek medical advice. Although rare, ED can be a side effect of more serious health conditions such as diabetes and heart disease.”
If your doctor thinks treatment is right for you, they may prescribe a tablet like Sildenafil as well as lifestyle changes. Sildenafil comes in three different dosages, the two most commonly prescribed being Sildenafil 50mg and Sildenafil 100mg.
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Available Sildenafil doses
Sildenafil is available in three doses; 25mg, 50mg and 100mg. The higher the dosage, the stronger its effects but this can also mean you’re more likely to experience side effects. Your doctor will prescribe the safest dose for you.
The three dosages:
| Strength | 25mg | 50mg | 100mg |
| Dosage type | Minimum | Standard | Maximum |
| Quantity | One tablet a day | One tablet a day | One tablet a day |
| Price per pack | From £16.00 | From £15.00 | From £25.00 |
What is the maximum dose of Sildenafil?
The maximum dose of Sildenafil is 100mg. As this is the highest dose, you shouldn’t take more than one tablet in 24 hours.
“Your doctor may prescribe a lower or higher dose depending on your health and how well Sildenafil is working for you. It's important to always follow the dosing instructions. - Dr Bhavini Shah
What dose of Sildenafil should I take?
The typical starting dose is 50mg. This dose is commonly recommended because of how well it typically works for most men. You may be prescribed a different dose based on your age, medical history, current medication, kidney function and BMI. Your doctor will offer you the best dose for you.
Taking Sildenafil 25mg
You may be prescribed the lower 25mg dose of sildenafil. This could be because you’re more prone to side effects or health conditions, which means it’s safer to try 25mg first. Lower doses still cause side effects, but these may be milder.
How to take sildenafil 25mg
- Take one tablet about 60 minutes before you’re going to have sex
- You need to be sexually aroused for sildenafil to work
- Do not take more than one dose a day
Sildenafil 25mg didn’t work for me. What should I do?
If 25mg doesn’t have the desired effect, firstly make sure you’re sexually aroused. Sildenafil won’t work on its own. You’ll also need to avoid drinking too much as well.
If sildenafil 25mg doesn’t work for you, you can also:
- Consider trying Sildenafil 25mg again. Doctors recommend taking ED tablets around eight times before changing treatment or upping the dose.
- Talk to your doctor about increasing the dose or message us in your Patient Record.
- You could try a different tablet which contains a different active ingredient. Speak to your doctor about what could work for you.
Taking Sildenafil 50mg
The most common Sildenafil dosage is 50mg. If you are using Sildenafil for the first time for erectile dysfunction, it is very likely that you will be prescribed this dosage.
You should use Sildenafil 50mg in the following way:
- Take only one tablet at a time
- Take the tablet one hour before you plan to have sex
- Do not eat a heavy meal beforehand
- Do not drink more than one or two units of alcohol beforehand
- Do not take more than one tablet in 24 hours
Sildenafil 50mg didn’t work for me. What should I do?
In controlled studies, Sildenafil 50mg was found to be effective in 74% of men with erectile dysfunction. So, it’s likely that you’ll have success with this treatment.
If you find that Sildenafil 50mg does not work for you the first time you take it, there are a few things you can do:
- Try Sildenafil on seven more occasions, making sure you take it exactly as recommended (doctors recommended trying ED tablets eight times before upping the dosage or changing to another treatment).
- If you are still having no success, talk to the doctor who prescribed it about switching to Sildenafil 100mg. If you ordered with us, send a message in your Patient Record.
- Consider trying a different ED tablet such as Cialis.
You should never alter the dosage of your Sildenafil without talking to your doctor.
Taking Sildenafil 100mg
It may be that your doctor initially prescribed you Sildenafil 100mg. Although it’s more common to start on the 50mg dosage and work up to 100mg if you have no success.
Sildenafil 100mg should be taken in the same way as the smaller dosage tablet: one hour before sex, and on a relatively empty stomach. There isn’t much difference between Sildenafil 100mg and 50mg, although in clinical trials, the higher dosage was seen to be 82% effective, as opposed to 74% effective.
The effects of Sildenafil 100mg do not last longer than the 50mg dosage, but they tend to be stronger. This means that side effects can be more pronounced as well.
Side effects associated with Sildenafil include:
- Headache
- Facial flushing
- Nausea
- Dizziness
- Stuffy nose
They will not affect everyone, but they are more likely when you are taking Sildenafil 100mg.
Sildenafil 100mg didn’t work for me. What should I do?
If you have found Sildenafil 100mg to be ineffective, you should talk to your prescribing doctor. They will probably encourage you to try it a few more times before you move onto something else.
Because 100mg is the highest dose available, you should never 'double up' on tablets or take more than one in 24 hours. Sildenafil 100mg is the highest safe dosage you can take – if it is ineffective, you should try another ED treatment.
How long does Sildenafil last?
When successful the effects of Sildenafil 50mg should last for 4 to 6 hours. During this time, you should be able to get an erection whenever you become sexually aroused.
The dosage you’re taking doesn’t change how long the effects will last for and the treatment won’t affect how long you last in bed.
Bear in mind that Sildenafil, and all other ED tablets, will only work if you become sexually aroused; it is not, in itself, an 'aphrodisiac'.
Alternative erectile dysfunction treatments
If Sildenafil doesn’t work for you there are alternative treatments. You should speak to your doctor about what’s best for you.
Alternative treatments for ED may contain different active ingredients but have a similar effect to Sildenafil. Alternative tablets and creams include:
In some cases, if the root of your ED is psychological, counselling may be helpful. ED caused by physical injury or an underlying condition, may improve with focused treatment, or lifestyle changes such as weight loss and exercise.
To find out more about Sildenafil, visit our online clinic.
Conclusion
Sildenafil is available in three different dosages – 25mg, 50mg and 100mg. Taken around 60 minutes before sex it helps men with erectile dysfunction get and keep an erection. The dose that’s right for you will depend on a few different factors. Start your online consultation today and our clinicians will make sure it’s safe for you to take.
