Choosing the best Viagra dosage

Finding the right Viagra dosage can take a little time but the potential benefits definitely make it worthwhile. You might start on the 50mg sildenafil dose but other dosages are available.

If you’re using the standard sildenafil dosage for ED and don’t feel like you’re quite realizing your “erectile potential,” then you should think about speaking to your prescriber to switch up your sildenafil dosage.

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Medically reviewed by
Mr Craig Marsh
Specialist Pharmacist Prescriber (UK)
on August 02, 2022.
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What Sildenafil dosages are there?

There are three different Sildenafil dosages prescribed for the treatment of erectile dysfunction. The different Viagra strengths give the option to raise or lower the amount of active ingredient (sildenafil citrate), depending on how your body reacts to the treatment.

Sildenafil 50mg is the middle dose and the one that most men will be introduced to. Starting here gives your clinician the opportunity to increase or decrease the dosage depending on how your body reacts to the treatment. It offers a great starting point, with 74% of patients in a fixed dose study reporting improved erections when using 50mg.

Sildenafil 25mg is the lowest dose. This dosage may be recommended if you have not tolerated Viagra well in the past, often highlighted by unwanted side effects. If you need to reduce your dosage to 25mg then don’t be put off, because a study still found 62% of participants that used this dose reported an improvement in their erections.

Sildenafil 100mg is the highest dosage on offer to treat ED. But don’t go thinking that you need the highest dose in order to have the hardest erections, because that isn’t how it works. Your clinician will want to find the lowest dose of the drug that does the job. This is to help keep the likelihood of side effects as low as possible. Your sildenafil dosage may be increased to 100mg if the lower dosage has not had the desired effect.

Sildenafil 20mg is used to treat pulmonary hypertension and isn’t licensed for the treatment of erectile dysfunction.

Why are there different Viagra dosages for ED?

What works well for you might not work well for someone else with ED. The availability of different sildenafil citrate dosages allows prescribers to level up and down where required. Your own personal recommended dose of Viagra will take lots of things into account, including your past medical history and current health and medications.

The Sildenafil 25mg dose can be a good starting point for men over the age of 65 with other medical conditions.

Sildenafil 50mg

If you’re being introduced to Viagra for the first time you’ll likely start with the sildenafil 50mg tablet. This is the median dose and is the recommended dose of Viagra for most men.

The Viagra 50mg dose can improve erection results but, because this dosage is the midpoint, it leaves room for a dosage change to be made if required.

It’s often referred to as the normal Viagra dose and that’s probably because, as we’ve mentioned, it is quite normal to start on 50mg. For this reason the non-prescription Viagra Connect dosage is also set at 50mg. This is an accessible starting point for many men, where they don’t have to attend a doctor consultation.

The 100mg dosage is never used as a starting point for men new to Viagra. There should be no need to start on the highest dosage.

Will all men start on Sildenafil 50mg?

Whilst Viagra 50mg tends to be the normal Viagra dose to start on, this isn’t the case for everyone. Sometimes a lower starting dose of 25mg will be suggested by a clinician. This route may be considered if you’re already taking certain medications for the treatment of kidney, liver or heart conditions. Or if your previous tolerance of sildenafil citrate 50mg was low.

No one will start on a 100mg dosage. The highest dose is reserved for particular cases where the generic Viagra dosage of 50mg has already been found to be lacking.

What if I get side effects on the Sildenafil 50mg dose?

Some men will experience unwanted side effects even on the median dose of Viagra. This sort of problem can sometimes be resolved by moving to the lower dose. When treating ED, the next dose down is 25mg. Your doctor will discuss making this change with you; you shouldn’t try to split pills. “In between” doses aren’t licensed for the treatment of ED in Canada. For example, Sildenafil 40mg is not used to treat erectile dysfunction.

Some of the more common side effects linked to sildenafil include headache, facial flushing, a stuffy nose, visual changes or dizziness. If you experience mild side effects, you may feel that the benefits outweigh the cons. However, should you experience a more serious side effect, such as a prolonged erection (priapism) or vision loss, then you need to seek immediate medical attention.

Sildenafil 100mg

Sildenafil 100mg and Viagra 100mg contain the maximum dose of sildenafil citrate for ED. Whilst you may think that the strongest Viagra pill is a good starting point to get your erections back on track, this isn’t the case.

The maximum dose of Viagra is not prescribed to first timers. The decision to increase the dose of sildenafil citrate to 100mg is usually suggested by the prescriber. But only after the smaller dose of 50mg has been trialed by the patient and found to be lacking.

If you think you need a strong Viagra dose, because the lower dose hasn’t worked how you were expecting, then you should consult your prescriber.

Is Viagra 100mg more effective?

In fixed dose studies the 100mg dosage of Sildenafil was found to improve erections for 82% of patients. This is slightly higher than the 50mg dosage (74%) and the 25mg dosage (62%).

Although the 100mg tablet is more potent and the most likely to be effective in giving erectile firmness, because there’s more of the active ingredient in it, with sildenafil 100mg side effects can be more likely. And the risk of these is higher for some men than others, depending on their tolerance of the drug.

So if a man who doesn’t need to take a dose as high as 100mg decides to take 100mg, the increased side effect risk could detract from the overall effectiveness rate. (If you get cumbersome side effects on a drug, then you could say it’s less effective for you overall.)

A man who only needs to take 50mg will keep their side effect risk low by taking the 50mg (thus enjoying a more effective use of the drug).

If you aren’t happy with your erections when taking the 50mg dosage, speak to your prescriber.

Is 20mg Cialis equal to 100mg Viagra?

They’re the two most well known ED drugs, so it’s common for men to compare Cialis and Viagra when trying to decide what will work best for them. The strongest dose of Cialis is 20mg while the strongest Viagra pill is 100mg. Cialis contains the active ingredient tadalafil whereas Viagra contains sildenafil citrate. Both drugs are from the PDE5 inhibitors category of medications and work in the same way.

Cialis is also generally well tolerated and has good outcomes rates for patients.

If your erections do not improve after you have tried Viagra, your prescriber may recommend an alternative oral ED treatment, such as Cialis.

Can I take Viagra daily?

Viagra should only be taken when you’re planning to have sex within the next hour. Only one Viagra pill should be taken in a 24 hour period.

If you’re looking for an ED pill that will cover you every day, for example if you want to have sex on a more spontaneous basis, then Cialis Daily may be a better option for you. The Cialis Daily pill allows those who take it to obtain a strong erection at any point within the 24 hours of taking it. As with all ED pills, sexual stimulation is still required for an erection to form.

Sildenafil 25mg

The sildenafil 25mg tablet is the lowest dose prescribed to treat ED. Sildenafil 25mg may be the initial starting dose for some men due to other ongoing health issues.

If you’re taking medication that could alter how your body metabolizes sildenafil then the prescriber could suggest starting at Viagra 25mg. This might be the case if you’re taking alpha-blockers for high blood pressure or antiretroviral drugs for HIV.

Also, as you get older your body may be slower at getting rid of sildenafil. Therefore, those over the age of 65 years may find that a starting dose of 25mg is sufficient. However, the Viagra dosage for a 70 year old can still be increased if the drug is well tolerated.

Who should take Viagra 20mg?

Viagra is not available at a dose of 20mg, but the generic version of it is. A doctor might prescribe Sildenafil 20mg for erectile dysfunction if they want to try you on a slightly lower dose. For example, if you’ve had a mild reaction to higher doses of sildenafil before, or if you’ve got a medical condition that means you’re more susceptible to side effects, you might be given the 20mg dose.

How to make sure you’re using the right Viagra dosage​

In order for your prescriber to select the best dosage for you, they need to have the full picture when it comes to your medical history. This includes any past and current health conditions and medications. Make sure that you inform them if you notice any side effects or if your treatment isn’t working like it should.

How to get the most out of your dose of Viagra

Of course you want to get the best out of your ED medication. In order to do this you should follow the instructions provided by the prescriber.

Viagra best-practice means avoiding heavy or fatty meals before you take your pill and taking it between 30-60 minutes before you intend to have sex. Remember Viagra will only get you hard when it’s combined with sexual stimulation.

Don’t split or double up on your pills. You should speak to your prescriber before making any changes to your dose.

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This page was medically reviewed by Mr Craig Marsh, Specialist Pharmacist Prescriber (UK) on August 02, 2022. Next review due on August 02, 2024.

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When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognized analytics or data body. Read more in our editorial policy.

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