Viagra is a prescription-only medication that is used to treat erectile dysfunction (ED) in men, and works for around 74% of men who try it. It works by increasing the blood flow to your penis, which helps men with ED to get and keep an erection when they are sexually aroused. Viagra takes up to 60 minutes to start working after you take it, and the effects last for up to 4 hours.

Why do I need to get a prescription?

Viagra is a prescription-only medication, which means that a doctor has to assess you to make sure it’s safe to take it. This is because it may react with certain medications, or may not be suitable if you have certain conditions. There is a type of Viagra called Viagra Connect which is available without a prescription from a doctor, but you will still need to go through an assessment with a pharmacist before you can get it.

What causes erectile dysfunction?

Erectile dysfunction is a common condition, and there are many different physical and psychological factors that can cause it. Common physical causes include obesity, heart disease, and high blood pressure. Common psychological causes of ED include stress, anxiety, and depression. Often there are several factors causing erectile dysfunction, not just a single cause. For more information, read our doctors’ advice on the causes of erectile dysfunction.

Viagra belongs to a class of medications called phosphodiesterase-5 (PDE-5) inhibitors. It works by temporarily increasing the blood flow to your penis, helping you to get and maintain an erection.

When you take Viagra, the active ingredient, sildenafil, relaxes the smooth muscles in the penis blood vessels, increasing blood flow which causes an erection.

Viagra only works if you are sexually aroused, it will not cause an erection on its own.

How effective is Viagra?

Clinical studies have shown that Viagra 50mg is effective in 74% of men who take it. The 25mg dose is 62% effective and the highest dose (100mg) is 82% effective, compared to taking a placebo (a pill without medication in it).

You should take Viagra around 1 hour before you plan to have sex. Swallow 1 Viagra tablet with a glass of water. You must only take 1 Viagra tablet every 24 hours.

Viagra is most effective if it is taken on an empty stomach. If you are going to eat with Viagra, choose a light meal rather than a heavy or greasy meal as this can increase the time it takes for Viagra to work.

Viagra is likely to be less effective if you take it with alcohol. Alcohol makes it more difficult to get an erection even if you don’t have erectile dysfunction. So, it is best to avoid or limit your alcohol intake when using Viagra.

When to take Viagra

Viagra takes approximately 30 to 60 minutes to work, so you should take it about 1 hour before you plan to have sex. Taking Viagra more than 4 to 6 hours before you want to have sex may mean your Viagra will have no effect and you will need to wait until the next day to try again.

How long does Viagra take to work?

Viagra usually takes 30 to 60 minutes to start working. So, it is recommended you take it around 1 hour before you want to have sex.

The following factors can affect how long it takes for Viagra to become effective:

• Arousal: You must be sexually stimulated for Viagra to take effect. Without arousal, Viagra will not work. Engaging in foreplay with your partner while you are waiting for Viagra to take effect can be a good way to speed up the process.
• Food: Some foods can delay the effects of Viagra, such as heavy, fatty, or greasy meals. You can take Viagra with or without food. If you take it with food, choosing a healthier, lighter option is a good idea.
• Alcohol: Alcohol can interfere with erectile function, even without Viagra. You should avoid taking alcohol when using Viagra.

How long does Viagra last?

Viagra lasts for up to 4 hours after you take it, although this can vary slightly. So, if you are planning to have sex in the evening, you shouldn’t take it too early in the day, especially as you can only take Viagra once in 24 hours. It’s recommended you take Viagra 1 hour before you want to have sex.

Several factors can affect how long Viagra lasts including, your age, health, diet, and alcohol consumption.

How often to take Viagra

Viagra should not be taken more than once a day. If you take more than your prescribed dose, like taking 2 doses in 1 day, this can increase the risk of side effects and potentially dangerous complications, including permanent damage to your penis.

If you think the Viagra dose you have been prescribed is too strong or too weak, speak to your doctor for advice. You should never take more or less Viagra to compensate.

Viagra comes in 3 different dosages, 50mg, 25mg, and 100mg. The higher the dosage the more of an effect it will have, but a higher dosage may also increase the chance of side effects. You may want to try different dosages to find which one works best for you.

Viagra 50mg

Viagra 50mg is the standard starting dose for most people, and is what we recommend if you’ve never tried Viagra before. 50mg is the most popular dosage of Viagra, and is effective for most men who try it.

Viagra 25mg

Viagra 25mg is the lowest dose of Viagra available. It is slightly less effective than Viagra 50mg, but it is also less likely to cause side effects. 25mg might be the best dosage for you if you tried 50mg and it worked for you, but you got side effects that you’d like to avoid. This dosage may also be offered if you are taking other medications to reduce the chance that the medications interact.

Viagra 100mg

Viagra 100mg is the highest dose of Viagra available. It is more effective than lower dosages of Viagra, but is also more likely to cause side effects. 100mg might be the best dosage for you if you tried 50mg and it didn’t work for you, and you didn’t get any side effects.

Read on for more information on the different dosages of Viagra, and which one is right for you.

You can request Viagra tablets online or get a prescription filled in most UK pharmacies. Branded versions of sildenafil, such as Viagra, are only available on the NHS in special circumstances.

Can I buy Viagra over the counter?

No, you must have a prescription or approval from a doctor to buy standard Viagra.

You can buy Viagra Connect over-the-counter without a prescription, either online or in a pharmacy. You will still need to answer a few health questions to make sure it is suitable for you.

Can I get Viagra on the NHS?

Viagra isn’t usually available on the NHS. Generic versions, such as sildenafil, are available on the NHS to treat erectile dysfunction.

Although not everyone will get side effects when they take Viagra, some will. Viagra side effects are more likely with higher doses. Some men may be more suited to a lower dose.

Common side effects (affecting up to 1 in 10 people) include:

• headaches
• feeling sick
• flushing
• facial flushing
• indigestion
• vision disturbances
• dizziness
• stuffy nose

Uncommon side effects (affecting up to 1 in 100 people) are:

• being sick
• skin rash
• eye irritation
• eye pain
• rapid heartbeat
• blood pressure changes
• dry mouth
• symptoms of the common cold
• nosebleeds
• tiredness

Rare side effects (affecting up to 1 in 1000 people) include:

• fainting
• stroke
• heart attack
• irregular heartbeat
• sudden loss of hearing
• dry nose
• seizures

If you experience any of the following serious side effects, stop taking Viagra immediately and call 999 or go to A&E:

• chest pains
• an allergic reaction (difficulty breathing, wheezing, swollen eyelids, face, lips, tongue)
• prolonged, painful erections
• a sudden loss of vision
• serious skin reactions
• seizures

You can learn more about the side effects of Viagra online or read about them in the patient leaflet that comes with the medication.

How long do Viagra side effects last?

Viagra side effects are usually mild and should only last a few hours to a day. Headaches caused by Viagra can last up to a week. Once the effects of Viagra have worn off, it’s likely the side effects will too. If you are worried about the side effects you are experiencing, contact your doctor for advice.

What to do if you get Viagra side effects

If you experience Viagra side effects and you are concerned or find them challenging to manage, speak to your doctor for advice. They may be able to prescribe an alternative dose or medication.

You can also report any side effects, including those not listed in the patient leaflet, via the Yellow Card Scheme.

If you experience any serious side effects, you must stop taking Viagra and go to A&E or call 999.

Viagra isn’t suitable for everyone. You should not take Viagra if you:

• are under 18
• were assigned female at birth
• do not have erectile dysfunction
• take or use other erectile dysfunction medications
• are allergic to any of the ingredients in Viagra
• have a severe heart or liver issue
• have recently had a heart attack or stroke
• have low blood pressure
• have an inherited eye disease called retinitis pigmentosa
• have lost your vision because of non-arteritic anterior ischaemic optic neuropathy (NAION)

You should let your doctor know if you have:

• sickle cell anaemia
• deformity of your penis (Peyronie’s disease)
• a stomach ulcer
• haemophilia

Viagra can interact with other medications which could make it less effective or cause dangerous side effects. Before taking Viagra, let your doctor know if you take:

• nitrates
• nitric oxide donors, e.g. amyl nitrate (poppers)
• riociguat
• any other PDE-5 inhibitors to treat pulmonary hypertension

There are several Viagra alternatives available if you aren’t suitable for Viagra, or want something that lasts longer than 4 hours. We look at the different erectile dysfunction treatments that you can get with a prescription and over-the-counter.

Cheaper Viagra

If you’re looking for a more affordable version of Viagra, consider sildenafil. Sildenafil is the active ingredient in Viagra and is sold under the same name as a generic (non-branded) erectile dysfunction treatment. It works in the same way, with similar effectiveness, speed, duration, side effects and so on.

Alternative prescription treatments

If you feel Viagra isn’t right for you or isn’t working, several other prescription-only erectile dysfunction medications may be more suitable. At Superdrug Online Doctor, we offer:

• Cialis: a long-lasting erectile dysfunction medication that contains the active ingredient tadalafil and lasts for up to 36 hours.
• Cialis Daily: a version of Cialis that’s taken every day so you’re always ready.
• Spedra: effective in as little as 15 minutes, Spedra is a fastest-acting erectile dysfunction treatment.
• Vardenafil: an effective treatment that works for up to 69% of men who take it.
• Vitaros: a topical cream that’s applied directly to the penis and gets to work in as little as 5 minutes.

Non-prescription options

Over-the-counter and non-prescription Viagra alternatives include:

• Viagra Connect: an over-the-counter version of Viagra that can be bought without a prescription.
• Superdrug sildenafil: a generic version of Viagra that can be bought without a prescription at Superdrug Pharmacies but you’ll still need to answer a few questions which will be checked by a pharmacist.
• Cialis Together: an over-the-counter version of Cialis that has longer-lasting effects than Viagra.
• Penis pumps: effective medical devices that encourage blood flow into the penis. They can be used with or without medications like Viagra. At Superdrug Online Doctor, we offer the Vaxaid V30 vacuum pump.

These options can be bought without prescriptions, but you can also request prescription Viagra alternatives online from Superdrug Online Doctor without having a previous prescription.

Will Viagra affect my fertility?

According to the NHS, there is no solid evidence that Viagra affects fertility in men or women. It actually may be helpful if you’re trying for a baby and want to have sex but need help getting and keeping an erection.

What happens if a woman takes Viagra?

It could cause serious side effects if you take Viagra and are a woman. Doctors can only approve Viagra for men – it is not available for women. Viagra is only licensed in the UK to be used by men. There’s also no evidence that it works for women.

Can I split Viagra tablets?

No, Viagra tablets should be swallowed whole with a glass of water. Do not split Viagra tablets. If you need a different dose, you should speak to a doctor.

Can I drink alcohol while taking Viagra?

Although you can drink alcohol, it isn’t a good idea as alcohol can make erectile dysfunction worse. It can also delay the effects of Viagra and increase the likelihood that you’ll experience side effects.

Can I take Viagra with other ED treatments?

No, you should not take Viagra with other oral or topical medications. You can, however, take Viagra while using a penis pump.

Does Viagra go out of date?

Viagra has a shelf life of around two years. You should not take Viagra if it is out of date. You will find the use-by date on the box and the medication strip.

How should I store Viagra?

Viagra should be stored in a cool, dry place out of the reach and sight of children. You should store Viagra in its original packaging to protect it from moisture.

What is the difference between Viagra and sildenafil?

Viagra and sildenafil are the same medication. Sildenafil is the active ingredient in Viagra and the generic version. Viagra is a branded form of sildenafil. Since it isn’t sold under a brand name, sildenafil tends to be cheaper.

Can you tell if a man has taken Viagra?

No, there are no tests that can prove a man has taken Viagra. If you have been with your partner for a while, they may notice differences, especially if they have been aware of your erectile issues. Taking Viagra or any other erectile dysfunction medication isn’t something to be ashamed of. Confiding in your partner and involving them on your journey might help, especially as you’ll need to be sexually stimulated for Viagra to work.