Sildenafil Tablets
Sildenafil is a cost-effective erectile dysfunction medication that contains the same active ingredient as Viagra.
(42)






Prices from £12.00
In stock. Simply fill in a brief consultation questionnaire and one of our doctors will review your request today.
Alternatives to sildenafil
-
Sildenafil is a generic treatment for erectile dysfunction (ED). It belongs to a group of drugs known as PDE5 inhibitors and contains the active ingredient sildenafil, which is the same ingredient in branded Viagra.
Sildenafil can help you to get and keep an erection. It works by by relaxing your blood vessels to allow more blood to flow to the penis. The recommended dose is 50mg an hour before sex. You may be started on a lower dose of 25mg if you take some medications. The highest dose is 100mg.
Prices
4 tablet(s) - £12.99
8 tablet(s) - £17.00
12 tablet(s) - £29.99
16 tablet(s) - £38.00
28 tablet(s) - £58.00
40 tablet(s) - £59.00
64 tablet(s) - £63.55
4 tablet(s) - £12.00
8 tablet(s) - £19.00
12 tablet(s) - £28.00
16 tablet(s) - £36.00
28 tablet(s) - £59.00
40 tablet(s) - £79.00
4 tablet(s) - £17.00
8 tablet(s) - £26.00
12 tablet(s) - £35.00
16 tablet(s) - £45.00
28 tablet(s) - £75.00
40 tablet(s) - £99.00



About sildenafil tablets
-
-
Sildenafil is a generic medication used to treat erectile dysfunction. It contains the active ingredient sildenafil, which is the same ingredient in Viagra. Sildenafil is a more affordable option for ED. It can help you get and keep an erection, as long as you are sexually aroused. It comes in tablet form and usually takes 30 to 60 minutes to work.
-
-
Sildenafil works by relaxing your blood vessels to allow more blood to flow to the penis. This blood flow triggers an erection and makes sildenafil an ideal treatment for erectile dysfunction.
Sildenafil blocks PDE-5 (phosphodiesterase type 5) enzymes in your penis to widen your blood vessels. There are other medicines that work in the same way, and these are called ‘PDE-5 inhibitors’.
Generally, you must be sexually aroused for sildenafil to work and give you an erection.
-
-
For best results: take sildenafil 1 hour before having sex. The effects of sildenafil can last for up to 4 to 5 hours.
Do not take more than 1 sildenafil tablet a day. Swallow it whole without chewing or crushing it. A glass of water will help you swallow it but you do not need to take it with food.
To help get the best results when taking sildenafil:
- avoid drinking grapefruit juice
- only have small amounts of alcohol (up to 3 units per day), as having a large amount of alcohol might make it difficult to get an erection
- take sildenafil on an empty stomach, as eating before taking sildenafil can make it work slower
If you have taken sildenafil and still cannot get an erection, do not take another dose. Try again the next day and make sure you avoid fatty foods and alcohol.
Erectile dysfunction can sometimes be caused by an underlying health reason, so speak to your doctor about a health check and other options if sildenafil does not work.
How long does it take to work?
You should take sildenafil 1 hour before you plan to have sex.
How long does sildenafil last?
Sildenafil lasts for around 4 hours after you take it. You can have more than 1 erection during this time, but only if you are sexually aroused.
What should I do if sildenafil isn't working?
If you think sildenafil is not working, you can speak to your doctor about increasing your dose. You should also follow the instructions on this page to make sure you are taking sildenafil for the best effect. You may need a different ED treatment.
How long does sildenafil stay in your system?
The effects of sildenafil last 4 to 5 hours. For the best results, you should:
- take sildenafil on an empty stomach, or avoid fatty meals
- avoid drinking alcohol, or restrict yourself to 3 units of alcohol only that day
- avoid grapefruit juice
-
-
The usual starting dose is 50mg, but you may be started on a lower dose of 25mg if you take some medications. The highest dose is 100mg, but you should not take more than prescribed. Generic Sildenafil has the same dosages as Viagra.
-
-
Sildenafil is an effective treatment for ED, but this does not mean it works every time. It usually takes an hour to work, so you should take it an hour before sex. It does not cure ED, but it can help you to get and keep an erection. You may need to take it a few times before you see the best effect.
-
-
You might have some side effects when taking sildenafil, but most of the time they should be minor.
Common side effects of taking sildenafil include:
- nausea (feeling sick)
- headaches
- indigestion
- hot flushes
- dizziness
- stuffy nose
- blurry vision
If you experience side effects that are uncomfortable or do not get better with time, you should speak to a doctor.
Uncommon side effects of taking sildenafil include:
- skin reactions, such as peeling or swollen skin
- seizures
- a painful erection that lasts over 4 hours
- chest pain
- changes in eyesight
If you experience any of these symptoms, stop taking sildenafil immediately and contact your doctor or call 999. For further information on very rare side effects, check the patient information leaflet contained in your medication packet or online.
You should also call 999 or go to A&E if you have a rare allergic reaction to sildenafil, where you may get these symptoms:
- wheezing
- tightness in your chest or throat
- trouble talking or breathing
- skin rash, such as red or itchy skin
- swelling of your face, lips, mouth, tongue or throat
-
-
You may be able to take sildenafil if you are over 18 years old and have erectile dysfunction.
You should not take sildenafil if you:
- are taking medication for chest pain (nitrates)
- ever had an allergic reaction to sildenafil or Viagra
- have low blood pressure
- have heart or kidney problems
- have recently had breast cancer or a stroke
- have a rare inherited eye disease
You should be careful about taking sildenafil and speak to a doctor first if you have:
- a stomach ulcer
- bleeding problems, or haemophilia
- sickle cell anaemia
- multiple myeloma
- any deformities in your penis, such as Peyronie's disease (curved penis)
Tell your doctor if any of these apply to you, to make sure that sildenafil is right for you.
-
-
Some medications can interact with sildenafil, which could make it less effective or unsafe for you to take. Speak to your doctor if you take any medications, especially:
- any medication to treat chest pain, such as nitrates
- nitric oxide donors, such as amyl nitrite
- riociguat, which is a treatment for chronic thromboembolic pulmonary hypertension
- protease inhibitors, you may need to be started on a lower dose of 25mg
- alpha blockers, which can be used for high blood pressure
You may need to avoid alcohol whilst taking sildenafil, as it can affect how well it works. If sildenafil is not working for you or you get side effects like dizziness, do not drink alcohol. You should also avoid drinking grapefruit juice when you take sildenafil.
-
-
Sildenafil may not be suitable for you or you may need a different treatment for your ED symptoms. You can get alternative erectile dysfunction treatments such as:
- tadalafil, a generic ED medication containing the active ingredient tadalafil
- Cialis, a branded version of tadalafil
- Levitra, which contains the active ingredient vardenafil
- Spedra, which contains the active ingredient avanafil
- Viagra, the branded version of sildenafil
You can also get an erectile dysfunction trial pack that contains 3 treatments. This allows you to try different ED treatments to see which works best for you.
-
-
Is sildenafil safe?
Yes, sildenafil is safe as long as you follow your doctor’s instructions and take it properly once it has been prescribed to you. For example, you should not take more than the recommended dose or take sildenafil with another erectile dysfunction medication.
You should not take sildenafil if you:
- take medication for chest pain (nitrates)
- have ever had an allergic reaction to sildenafil or Viagra
- have low blood pressure
- have heart or kidney problems
- have recently had breast cancer or a stroke
- have a rare inherited eye disease
Additionally, speak to a doctor beforehand if you have:
- a stomach ulcer
- a bleeding disorder, like haemophilia
- sickle cell anaemia
- multiple myeloma
- any deformities in your penis, such as a significant bend or curve (Peyronie's disease)
When you request sildenafil through ZAVA, we will ask about these conditions so our doctors can check that sildenafil is safe and suitable for you.
You should always read the patient information leaflet included with any prescribed medication before taking it for the first time.
Is sildenafil the same as Viagra?
Yes, sildenafil and Viagra are the same. They both contain the same active ingredient, sildenafil, and work in the same way. Sildenafil is simply the generic, unbranded version of Viagra. Generic medications are typically less expensive than branded medications.
The other key difference between sildenafil and Viagra is their appearance. Viagra pills have a distinct blue, diamond shaped appearance while generic sildenafil pills are white and round.
Is sildenafil as effective as Viagra?
Sildenafil is just as effective as Viagra because sildenafil and Viagra both contain the same active ingredient (sildenafil) and work the same way. Viagra is the brand name version of sildenafil, and they both have the same amount of sildenafil in each tablet and work for the same amount of time.
Can I get sildenafil without a prescription?
You cannot buy sildenafil without a prescription, but you can get it online with ZAVA. Sildenafil is available through the NHS. You’ll need to book an appointment with your doctor to get a prescription.
Viagra Connect (50mg sildenafil) is available without a prescription, as it is an over the counter version of Viagra that you can buy online or in a pharmacy.
You might find other products with sildenafil available to buy on the internet for ED treatment. However, Kamagra or Kamagra Oral Jelly are not regulated in the UK and their safety is not assured.
Can sildenafil make you last longer in bed?
Sildenafil cannot make you last longer in bed. When you are aroused, sildenafil can help you get and maintain an erection but it cannot stop you from ejaculating.
Premature ejaculation is when you ejaculate too early during sex. If you find you are ejaculating within the first few minutes of sex, there are other treatments you can try, such as Emla cream or Priligy tablets.
Can sildenafil be taken daily?
Yes, you can take sildenafil daily but you must not take more than 1 pill a day.
Can I cut sildenafil tablets in half?
You can cut or split a sildenafil pill in half, if you wish. For example, if you can’t swallow a whole pill or if you only want to take half a pill at a time.
However, you should:
- check this is safe to do with your doctor beforehand
- use a pill splitter or pill cutter device to do this properly and safely, instead of a knife or scissors
- split one pill at a time close before you plan to take it
- store any split pills in a sealed container away from sunlight
Please note, not all pills or tablets can be split or cut in half. This includes those that are scored and appear like they can be split.
Can sildenafil tablets be crushed?
You should not crush a sildenafil pill when taking it. Instead, swallow it whole without crushing or chewing it.
How long does sildenafil stay in your system?
The effects of sildenafil last 4 to 5 hours. For the best results, you should:
- take sildenafil on an empty stomach, or avoid fatty meals
- avoid drinking alcohol, or restrict yourself to 3 units of alcohol only that day
- avoid grapefruit juice
Will sildenafil work faster if I chew it?
No, there is no way to make sildenafil work faster. This includes chewing a pill.
Can I drink alcohol with sildenafil?
Yes, but you should limit yourself to 3 units of alcohol on any day you take sildenafil. If you drink large amounts of alcohol, you may find it difficult to get an erection and lose it during sex, whether you take erectile dysfunction medication or not.
As a guide, 3 units of alcohol is equivalent to either:
- 3 single shots of gin, rum, vodka, whisky, tequila or sambuca (25ml, ABV 40% per shot)
- 1 pint of higher strength lager, beer or cider (ABV 5.2%)
- 1 large glass of red/white/rosé wine (250ml, ABV 12%)
Can I take sildenafil on an empty stomach?
You can take sildenafil on an empty stomach but it is not always necessary. Taking sildenafil with food or after eating a meal may cause it to work more slowly.
Does sildenafil cause low blood pressure?
Sildenafil can cause a small drop in blood pressure because it works by relaxing blood pressure in your arteries.
If you have low blood pressure (hypotension) or you take medication for chest pains (nitrates), it is not safe to take sildenafil. This is because your blood pressure can drop too low as a result.
A doctor will check that sildenafil is safe for you by asking you about any medical conditions you have or medications you’re taking before prescribing it to you. If you request sildenafil through ZAVA, one of our doctors will check this as part of your online consultation.

Babak studied medicine at King’s College London and graduated in 2003, having also gained a bachelor’s degree in Physiology during his time there. He completed his general practice (GP) training in East London, where he worked for a number of years as a partner at a large inner-city GP practice. He completed the Royal College of GPs membership exam in 2007.
Meet our doctorsLast reviewed: 29 Jul 2022
-
About sildenafil (Viagra), National Health Service [accessed May 2022]
-
Erectile dysfunction (impotence), National Health Service [accessed May 2022]
-
Sildenafil 50 mg film-coated tablets, Patient Information Leaflet, EMC[accessed May 2022]
-
Sildenafil, NICE/British National Formulary [accessed May 2022]
-
Sildenafil, Summary of Product Characteristics, EMC [accessed May 2022]