Patient leaflet - Sildenafil 20 mg film-coated tablets
1. What Sildenafil 20 mg is and what it is used for
Sildenafil 20 mg contains the active substance sildenafil which belongs to a group of medicines called phosphodiesterase type 5 (PDE5) inhibitors. Sildenafil 20 mg brings down blood pressure in the lungs by widening the blood vessels in the lungs. Sildenafil 20 mg is used to treat adults and children and adolescents from 1 to 17 years old with high blood pressure in the blood vessels in the lungs (pulmonary arterial hypertension).
2. What you need to know before you take Sildenafil 20 mg
Do not take Sildenafil 20 mg:
if you are allergic to sildenafil or any of the other
ingredients of this medicine (listed in section 6).
if you are taking medicines containing nitrates,
or nitric oxide donors such as amyl nitrate ("poppers"). These medicines are often given for relief of chest pain (or "angina pectoris"). Sildenafil 20 mg can cause a serious increase in the effects of these medicines. Tell your doctor if you are taking any of these medicines. If you are not certain, ask your doctor or pharmacist.
if you are taking riociguat. This drug is used to
treat pulmonary arterial hypertension (i.e., high blood pressure in the lungs) and chronic thromboembolic pulmonary hypertension (i.e., high blood pressure in the lungs secondary to blood clots). PDE5 inhibitors, such as Sildenafil 20 mg, have been shown to increase the hypotensive effects of this medicine. If you are taking riociguat or are unsure, tell your doctor.
if you have recently had a stroke, a heart attack
or if you have severe liver disease or very low blood pressure (< 90/50 mmHg).
if you are taking a medicine to treat fungal
infections such as ketoconazole or itraconazole or medicines containing ritonavir (for HIV).
if you have ever had loss of vision because of a
problem with blood flow to the nerve in the eye called non-arteritic anterior ischaemic optic neuropathy (NAION).
Warnings and precautions
Talk to your doctor before taking Sildenafil 20 mg if you:
have a disease due to a blocked or narrow vein in
the lungs rather than a blocked or narrow artery.
- have a severe heart problem.
have a problem with the pumping chambers of
your heart.
have high blood pressure in the blood vessels in
the lungs.
- have low blood pressure at rest.
lose a large amount of body fluids (dehydration)
which can occur when you sweat a lot or do not drink enough liquids. This can happen if you are sick with a fever, vomiting, or diarrhoea.
have a rare inherited eye disease (retinitis
pigmentosa).
have an abnormality of red blood cells (sickle
cell anaemia), cancer of blood cells (leukaemia), cancer of bone marrow (multiple myeloma), or any disease or deformity of the penis.
currently have a stomach ulcer, a bleeding
disorder (such as haemophilia) or problems with nose bleeds.
take medicines for erectile dysfunction. When used to treat male erectile dysfunction (ED), the following visual side effects have been reported with PDE5 inhibitors, including sildenafil at an unknown frequency; partial, sudden, temporary, or permanent decrease or loss of vision in one or both eyes.
If you experience sudden decrease or loss of vision, stop taking Sildenafil 20 mg and contact your doctor immediately (see also section 4). Prolonged and sometimes painful erections have been reported in men after taking sildenafil. If you have an erection, which lasts continuously for more than 4 hours, stop taking Sildenafil 20 mg and contact your doctor immediately (see also section 4).
Special considerations for patients with kidney or liver problems
You should tell your doctor if you have kidney or liver problems, as your dose may need to be adjusted.
Children
Sildenafil 20 mg should not be given to children below 1 year of age.
Other medicines and Sildenafil 20 mg
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines.
Medicines containing nitrates, or nitric oxide
donors such as amyl nitrate (“poppers”). These medicines are often given for relief of angina pectoris or “chest pain” (see section 2. Before you take Sildenafil 20 mg).
Tell your doctor or pharmacist if you are already
taking riociguat.
Therapies for pulmonary hypertension (e.g.
bosentan, iloprost).
Medicines containing St. John's Wort (herbal
medicinal product), rifampicin (used to treat bacterial infections), carbamazepine, phenytoin and phenobarbital (used, among others, to treat epilepsy).
Blood thinning medicines (for example warfarin)
although these did not result in any side effect.
Medicines containing erythromycin, clarithro-
mycin, telithromycin (these are antibiotics used to treat certain bacterial infections), saquinavir (for HIV) or nefazodone (for mental depression), as your dose may need to be adjusted.
Alpha-blocker therapy (e.g. doxazosin) for the
treatment of high blood pressure or prostate problems, as the combination of the two medicines may cause symptoms resulting in the lowering of your blood pressure (e.g. dizziness, light headedness).
Medicines containing sacubitril/valsartan, used
to treat heart failure.
Sildenafil 20 mg with food and drink
You should not drink grapefruit juice while you are being treated with Sildenafil 20 mg.
Pregnancy and breast-feeding
If you are pregnant, or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.
Sildenafil 20 mg should not be used during pregnancy unless strictly necessary.
Sildenafil 20 mg should not be given to women of child bearing potential unless using appropriate contraceptive methods.
Sildenafil 20 mg passes into your breast milk at very low levels and would not be expected to harm your baby.
Driving and using machines
Sildenafil 20 mg can cause dizziness and can affect vision. You should be aware of how you react to the medicine before you drive or use machines.
Sildenafil 20 mg contains lactose
If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicinal product.
Sildenafil 20 mg contains sodium
Sildenafil 20 mg tablets contain less than 1 mmol sodium (23 mg) per tablet, that is to say essentially 'sodium-free'.
3. How to take Sildenafil 20 mg
Always take this medicine exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.
For adults, the recommended dose is 20 mg three times a day (taken 6 to 8 hours apart) taken with or without food.
Use in children and adolescents
For children and adolescents aged 1 year to 17 years old, the recommended dose is either 10 mg three times a day for children and adolescents ≤20 kg or 20 mg three times a day for children and adolescents > 20 kg, taken with or without food. Higher doses should not be used in children. This medicine should be used only in case of administration of 20 mg three times a day. Other pharmaceutical forms may be more appropriate for administration to patients ≤ 20 kg and other younger patients who are not able to swallow tablets.
If you take more Sildenafil 20 mg than you should
You should not take more medicine than your doctor tells you to.
If you take more medicine than you have been told to take contact your doctor immediately. Taking more Sildenafil 20 mg than you should may increase the risk of known side effects.
If you forget to take Sildenafil 20 mg
If you forget to take Sildenafil 20 mg film-coated tablet, take a dose as soon as you remember, then continue to take your medicine at the usual times. Do not take a double dose to make up for a forgotten dose.
If you stop taking Sildenafil 20 mg
Suddenly stopping your treatment with Sildenafil 20 mg may lead to your symptoms getting worse. Do not stop taking Sildenafil 20 mg unless your doctor tells you to. Your doctor may tell you to reduce the dose over a few days before stopping completely. If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
4. Possible side effects
Like all medicines, Sildenafil 20 mg can cause side effects, although not everybody gets them. If you experience any of the following side effects, you should stop taking Sildenafil 20 mg and contact a doctor immediately (see also section 2):
if you experience sudden decrease or loss of
vision (frequency not known)
if you have an erection, which lasts conti-
nuously for more than 4 hours.
Prolonged and sometimes painful erections have
been reported in men after taking sildenafil (frequency not known).
Adults
Side effects reported very commonly (may affect more than 1 in 10 people) were headache, facial flushing, indigestion, diarrhoea and pain in the arms or legs.
Side effects reported commonly (may affect up to 1 in 10 people) included: infection under the skin, flu-like symptoms, inflammation of the sinuses, reduced number of red blood cells (anaemia), fluid retention, difficulty sleeping, anxiety, migraine, shaking, “pins and needles”-like sensation, burning sensation, reduced sense of touch, bleeding at the back of the eye, effects on vision, blurred vision and light sensitivity, effects on colour vision, eye irritation, bloodshot eyes /red eyes, vertigo, bronchitis, nosebleed, runny nose, cough, stuffy nose, stomach inflammation, gastroenteritis, heartburn, piles, abdominal distension, dry mouth, hair loss, redness of the skin, night sweats, muscle aches, back pain and increased body temperature.
Side effects reported uncommonly (may affect 1 in 100 people) included: reduced sharpness of vision, double vision, abnormal sensation in the eye, penile bleeding, presence of blood in semen and/or urine, and breast enlargement in men.
Skin rash and sudden decrease or loss of hearing and decreased blood pressure have also been reported at an unknown frequency (frequency cannot be estimated from the available data).
Children and adolescents
The following serious adverse events have been reported commonly (may affect up to 1 in 10 people); pneumonia, heart failure, right heart failure, heart related shock, high blood pressure in the lungs, chest pain, fainting, respiratory infection, bronchitis, viral infection in the stomach and intestines, urinary tract infections and tooth cavities.
The following serious adverse events were considered to be treatment related and were reported uncommonly (may affect up to 1 in 100 people), allergic reaction (such as skin rash, swelling of the face, lips and tongue, wheezing, difficulty breathing or swallowing), convulsion, irregular heart-beat, hearing impairment, shortness of breath, inflammation of the digestive tract, wheezing due to disrupted airflow.
Side effects reported very commonly (may affect more than 1 in 10 people) were headache, vomiting, infection of the throat, fever, diarrhoea, flu and nosebleed.
Side effects reported commonly (may affect up to 1 in 10 people) were nausea, increased erections, pneumonia and runny nose.
Reporting of side effects
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.
5. How to store Sildenafil 20 mg
Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated on the carton after EXP. The expiry date refers to the last day of that month.
Store below 25°C.
Store in the original package in order to protect from moisture.
Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help to protect the environment.
6. Contents of the pack and other information
What Sildenafil 20 mg contains
- The active substance is sildenafil. Each tablet contains 20 mg of sildenafil (as sildenafil citrate).
The other ingredients are:
Tablet core: Cellulose, microcrystalline, Calcium hydrogen phosphate (anhydrous), Croscarmellose sodium, Silica colloidal, Magnesium stearate.
Film coat: Hypromellose, Titanium dioxide (E171), Lactose monohydrate, Triacetin
What Sildenafil 20 mg looks like and contents of the pack
Sildenafil 20 mg film-coated tablets are white, 6.5 mm round shaped film-coated tablets, debossed with "1A4" on one side and plain on other side. The tablets are provided in PVC/aluminium blister packs containing 1 tablet, 10 tablets, 90 tablets and 300 tablets.
Not all pack sizes may be marketed.
Marketing Authorization Holder and Manufacturer
Marketing Authorization Holder:
Umedica Laboratories UK Ltd
Office No. G42
The Panorama Park Street
Ashford, England
TN24 8DF
Manufacturer:
Elara Pharmaservices Limited
5 Garden Court,
Lockington Hall, Main Street,
Lockington Derby, United Kingdom,
DE74 2RH
This medicinal product is authorised under the following names:
Sildenafil 20 mg film-coated tablets –
PL 60528/0028
This leaflet was last revised in February 2026. Sildenafil 20 mg film-coated tablets Sildenafil
Package leaflet: Information for the patient
Umedica Laboratories UK Ltd
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