- Treatment for erectile dysfunction with Viagra®
- Access Viagra® following an online medical consultation
- What is Viagra®?
- What is the active substance in Viagra®?
- Who is the treatment suitable for?
- What dosages are available?
- Can I change doses myself?
- How should Viagra® be taken?
- What can affect the effect of Viagra®?
- When should Viagra® not be used?
- What side effects can occur?
- Viagra® active substance and excipients
- Viagra® patient information leaflet
Treatment for erectile dysfunction with Viagra®
Viagra® is a prescription-only medicine (POM) from Pfizer used in adult men for the treatment of erectile dysfunction (ED). ED is defined as the persistent inability to achieve or maintain an erection sufficient for satisfactory sexual activity.
Viagra® contains sildenafil (as sildenafil citrate), which belongs to a group of medicines known as PDE-5 inhibitors. It works by helping to increase blood flow to the penis during sexual stimulation. Viagra® does not cause an erection on its own; sexual stimulation is required.
Viagra® film-coated tablets are available in different strengths. The dose prescribed depends on individual health factors and must be determined by a clinician following a medical assessment.
Access Viagra® following an online medical consultation
Start the online consultation and complete a confidential medical questionnaire.
A UK-registered healthcare professional will review your information and determine whether Viagra® may be appropriate. If suitable, a prescription can be issued following clinical assessment.
Important information
DoktorABC UK is a digital health platform that connects patients with independent, UK-registered healthcare professionals. DoktorABC UK does not provide medical care, issue prescriptions or dispense medicines. All clinical decisions are made by the prescribing clinician following an individual medical assessment.
What is Viagra®?
Viagra® is a prescription-only medicine used to treat erectile dysfunction in adult men. It contains sildenafil (as sildenafil citrate). Viagra® may help some men achieve and maintain an erection when sexually stimulated.
What is the active substance in Viagra®?
The active substance is sildenafil citrate. Sildenafil inhibits the enzyme PDE-5, which plays a role in regulating blood flow in the penis. By inhibiting PDE-5, sildenafil supports the natural erectile response to sexual stimulation.
Who is the treatment suitable for?
Viagra® may be considered for adult men (aged 18 and over) with erectile dysfunction, following a medical assessment.
Treatment may not be suitable for everyone. A clinician will consider factors such as cardiovascular health, current medicines and relevant medical history before prescribing.
What dosages are available?
Viagra® film-coated tablets are available in the following strengths:
- 25 mg
- 50 mg
- 100 mg
The recommended starting dose is often 50 mg, taken as needed, but dosing must be individualised by the prescribing clinician. Do not take more than one dose per day.
Can I change doses myself?
No. Dose adjustments should be made only in consultation with the prescribing clinician.
How should Viagra® be taken?
Viagra® is usually taken about 1 hour before sexual activity. The tablet should be swallowed whole with water.
It can be taken with or without food. However, a heavy meal may delay the onset of effect.
What can affect the effect of Viagra®?
The effect of sildenafil can vary depending on individual factors and circumstances. Examples that may influence response include:
- Taking it with a heavy meal (may delay onset)
- Alcohol (may reduce the ability to achieve an erection and may increase side effects)
- Underlying health conditions (e.g., diabetes, cardiovascular disease)
- Incorrect timing or dose (your clinician can advise)
When should Viagra® not be used?
Viagra® must not be used if you:
- are allergic to sildenafil or any ingredient of the product
- take nitrate medicines for chest pain (angina)
- use nitric oxide donors such as amyl nitrite ("poppers")
- take riociguat
- have certain serious heart or liver conditions
- have recently had a heart attack or stroke
- have very low blood pressure
- have certain rare inherited eye conditions or a history of sudden vision loss (e.g., NAION)
Always inform your clinician about your full medical history and current medicines before starting treatment.
What side effects can occur?
Like all medicines, Viagra® can cause side effects, although not everyone experiences them.
Very common side effects
- Headache
Common side effects
- Flushing
- Indigestion
- Nasal congestion
- Dizziness
- Visual disturbances (altered colour perception, blurred vision)
Serious side effects (seek urgent medical help)
- Chest pain
- Sudden loss of vision or hearing
- Prolonged or painful erection lasting more than 4 hours (priapism)
- Severe allergic reactions (sudden wheezing, breathing difficulties, swelling of eyelids, face, lips or throat)
- Severe skin reactions
- Seizures
Reporting side effects (UK)
Suspected adverse reactions can be reported via the MHRA Yellow Card scheme.
Viagra® active substance and excipients
Active substance:
- Sildenafil (as sildenafil citrate), available in 25 mg, 50 mg and 100 mg strengths
Other ingredients:
- Microcrystalline cellulose
- Calcium hydrogen phosphate
- Croscarmellose sodium
- Magnesium stearate
- Hypromellose
- Titanium dioxide (E 171)
- Lactose monohydrate
- Triacetin
- Indigo carmine aluminium lake (E 132)
Manufacturer:
Pfizer Limited
Viagra® patient information leaflet
The UK patient information leaflet for Viagra® is available via the electronic Medicines Compendium (eMC).
Frequently asked questions
How long does Viagra® take to work?
Viagra® typically starts working within 30–60 minutes, but timing varies between individuals.
Does Viagra® work without sexual stimulation?
No. Sexual stimulation is required for Viagra® to be effective.
How long do the effects last?
The effects may last for up to around 4–5 hours, although this varies between individuals.
Can I take Viagra® more than once per day?
No. Do not take Viagra® more than once per day.
What is the difference between Viagra® and sildenafil?
Viagra® is a brand of sildenafil (sildenafil citrate). Generic sildenafil contains the same active substance and works in the same way.
Is Viagra available without a prescription in the UK?
In the UK, Viagra® is a prescription-only medicine (POM). There is also Viagra Connect (sildenafil 50 mg), which was reclassified by the MHRA as a Pharmacy (P) medicine and may be supplied following assessment by a pharmacist. This page relates to Viagra® (POM).
Can I take Viagra® with alcohol?
Moderate alcohol intake is advised. Excessive alcohol consumption may reduce the ability to achieve an erection and may increase the risk of side effects.
Can I take Viagra® if I have high blood pressure?
Viagra® may be suitable if high blood pressure is well controlled. However, if you take certain blood pressure medicines, particularly alpha blockers, inform your clinician as dose adjustment may be required.
Can I drive after taking Viagra®?
Viagra® may cause dizziness or visual disturbances. Do not drive or operate machinery if affected.
How should I store Viagra®?
Store below 30°C, in the original packaging to protect from moisture. Keep out of the reach of children. Do not use after the expiry date.
Leaflet info
The Patient Information Leaflet (PIL) is the leaflet included in the pack with a medicine. It is written for patients and gives information about taking or using a medicine. It is possible that the leaflet in your medicine pack may differ from the PDF-version from this website because it may have been updated since your medicine was packaged or the medicine is from another brand.
