Sildenafil
Sildenafil improves penile blood flow response to sexual stimulation in erectile dysfunction, and is used in specialist care for some types of pulmonary hypertension at different dosing schedules. The two uses are not interchangeable — use only the strength and frequency prescribed.
This medicine is part of the Blood pressure, cholesterol & related category.
Generic name: sildenafil
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Sildenafil improves penile blood flow response to sexual stimulation in erectile dysfunction, and is used in specialist care for some types of pulmonary hypertension at different dosing schedules.
How long does it take to work?
Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review.
What are common side effects?
Headache, flushing, indigestion, nasal congestion, or temporary colour-tinged vision.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Sildenafil with paracetamol or ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
More about what Sildenafil is used for
Sildenafil improves penile blood flow response to sexual stimulation in erectile dysfunction, and is used in specialist care for some types of pulmonary hypertension at different dosing schedules.
The two uses are not interchangeable — use only the strength and frequency prescribed.
How does Sildenafil work, and how long does it take to work?
It inhibits phosphodiesterase-5, increasing nitric oxide pathway effects on blood vessels in penile and lung circulations as relevant.
Sexual stimulation is still needed for erectile effect.
How and when should you take Sildenafil?
For erectile dysfunction, often taken about an hour before activity, maximum once daily unless told otherwise.
Avoid heavy fatty meals around dosing which may delay absorption.
What are the common side effects of Sildenafil?
Headache, flushing, indigestion, nasal congestion, or temporary colour-tinged vision.
Serious side effects of Sildenafil — when to get urgent help
Seek emergency help for chest pain — do not use nitrates if you recently took sildenafil. Prolonged painful erection over four hours needs urgent care.
Sudden hearing or vision loss is rare but urgent.
What if you miss a dose of Sildenafil?
Usually taken as needed rather than strict daily timing for ED; pulmonary hypertension schedules are fixed — follow that plan if applicable.
Who should not take Sildenafil?
Nitrate therapy, riociguat, severe recent heart attack or stroke, and some eye conditions such as non-arteritic anterior ischaemic optic neuropathy risk factors need specialist input.
Can you take paracetamol or ibuprofen with Sildenafil? — other interactions
Nitrates and GTN are dangerous combinations. Alpha-blockers for prostate can cause hypotension if taken together without spacing — prescriber plans matter.
Sildenafil in pregnancy and breastfeeding
Pulmonary hypertension use in pregnancy is highly specialised.
Blood tests and monitoring on Sildenafil
Blood pressure checks if cardiovascular risk; review if headaches or vision changes persist.
What might your GP prescribe instead of Sildenafil?
Tadalafil, vardenafil, vacuum devices, or psychosexual counselling may be discussed.
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Reviewed by UK registered pharmacists for accuracy and clarity. Content is informational only.
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Frequently asked questions about Sildenafil
People also ask — common Google searches
- What is Sildenafil used for?
- Sildenafil improves penile blood flow response to sexual stimulation in erectile dysfunction, and is used in specialist care for some types of pulmonary hypertension at different dosing schedules. The two uses are not interchangeable — use only the strength and frequency prescribed.
- How long does Sildenafil take to work?
- Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review. Always follow your prescriber’s follow-up plan.
- Can you take Sildenafil with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Sildenafil with Paracetamol or Ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
- What are the side effects of Sildenafil?
- Headache, flushing, indigestion, nasal congestion, or temporary colour-tinged vision. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Can I take sildenafil with ramipril?
- Often yes if blood pressure is stable and you are not on nitrates — your GP checks cardiovascular fitness first.
- Is generic sildenafil as good as Viagra?
- Generics contain the same active ingredient; tablet coatings and fillers can differ slightly but effectiveness should match the same dose.
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Often used with
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