Finasteride
Finasteride shrinks prostate size over months in benign enlargement and is used at lower doses for male-pattern hair loss in men when prescribed. Different tablet strengths are not interchangeable — use the indication on your prescription.
This medicine is part of the Blood pressure, cholesterol & related category.
Generic name: finasteride
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?
Finasteride shrinks prostate size over months in benign enlargement and is used at lower doses for male-pattern hair loss in men when prescribed.
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?
Reduced libido, erectile dysfunction, breast tenderness, or mood changes reported by some men.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Finasteride 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 Finasteride is used for
Finasteride shrinks prostate size over months in benign enlargement and is used at lower doses for male-pattern hair loss in men when prescribed.
Different tablet strengths are not interchangeable — use the indication on your prescription.
How does Finasteride work, and how long does it take to work?
It blocks conversion of testosterone to dihydrotestosterone, reducing prostate growth drive and hair follicle miniaturisation in androgenic alopecia.
Effects take months for hair and prostate symptom benefits.
How and when should you take Finasteride?
Swallow tablets whole; women who are or may be pregnant should not handle crushed tablets.
Continue as directed — stopping reverses benefits over time.
What are the common side effects of Finasteride?
Reduced libido, erectile dysfunction, breast tenderness, or mood changes reported by some men.
Serious side effects of Finasteride — when to get urgent help
Seek help for testicular pain, depression with suicidal thoughts, or severe allergic reactions.
What if you miss a dose of Finasteride?
Take when remembered unless nearly time for next; do not double.
Who should not take Finasteride?
Pregnancy — teratogenic to male foetus if exposed via medication handling. Not for women for hair loss.
Can you take paracetamol or ibuprofen with Finasteride? — other interactions
Few major interactions; always list all medicines for prostate care reviews.
Finasteride in pregnancy and breastfeeding
Pregnant women must avoid contact with broken tablets.
Blood tests and monitoring on Finasteride
PSA blood tests may be interpreted differently on finasteride — tell clinicians you take it.
What might your GP prescribe instead of Finasteride?
Dutasteride, alpha-blockers, or hair transplant 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 Finasteride
People also ask — common Google searches
- What is Finasteride used for?
- Finasteride shrinks prostate size over months in benign enlargement and is used at lower doses for male-pattern hair loss in men when prescribed. Different tablet strengths are not interchangeable — use the indication on your prescription.
- How long does Finasteride 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 Finasteride with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Finasteride 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 Finasteride?
- Reduced libido, erectile dysfunction, breast tenderness, or mood changes reported by some men. See the sections below for more detail, including serious side effects and when to seek urgent help.
- How long for finasteride to thicken hair?
- Often six months or more before visible change; photography helps track progress.
- Does finasteride affect PSA screening?
- It lowers PSA roughly by half in many men — your GP adjusts interpretation for prostate cancer blood tests.
Need personalised advice?
Your local pharmacist or GP surgery can help with questions about your medicines, side effects, and alternatives that may be suitable for you.
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