Finas

Indications

Finasteride is used in men to treat an enlarged prostate (benign prostatic hyperplasia, BPH), easing urinary symptoms and lowering the risk of urine retention and prostate surgery. At a lower strength it is used to treat male pattern hair loss on the crown and middle of the scalp.

How It Works

Finasteride blocks the enzyme 5-alpha reductase, which converts testosterone into dihydrotestosterone (DHT). DHT drives prostate growth and shrinks hair follicles in men prone to baldness. Lowering DHT gradually shrinks the prostate and can slow hair loss and help some hair regrow.

Dosage and Administration

• Enlarged prostate: 5 mg once daily, alone or with an alpha blocker such as Tamsulosin.
• Male pattern hair loss: 1 mg once daily.

Take with or without food. It may take 3 to 6 months to see benefit for the prostate and 3 to 6 months or more for hair. Benefit for hair is lost within about a year of stopping.

Interactions

No major interactions are common. It lowers the result of the PSA blood test (used to screen for prostate cancer) by about half, so tell your doctor you take it before any PSA test.

Contraindications

Finasteride is not for women or children. Do not use if you are allergic to it. Women who are or may become pregnant must not take it or handle crushed or broken tablets.

Side Effects

Possible side effects include reduced sex drive, difficulty getting an erection, less semen during ejaculation, breast tenderness or enlargement, and rash. Low mood and depression have been reported; in some men sexual side effects have continued after stopping.

Get urgent medical help if you have swelling of the lips, face or throat, difficulty breathing, a breast lump, nipple discharge or breast pain, or low mood with thoughts of self-harm.

Pregnancy and Lactation

Finasteride can cause abnormal development of the genitals of a male unborn baby. Pregnant women, and women who could become pregnant, must not take it or touch crushed or broken tablets. Coated whole tablets are safe to handle. It is not used by women, so breastfeeding advice does not apply.

Precautions and Warnings

Your doctor should rule out prostate cancer before and during treatment. A rise in PSA while on Finasteride needs checking. Use with care in liver disease. Do not donate blood during treatment and for some time after stopping, so the blood is not given to a pregnant woman. Report any mood changes.

Overdose

Single large doses have not caused serious problems. Seek medical advice if a large amount is taken.

Therapeutic Class

5-alpha reductase inhibitor.

Storage

Store below 30°C in a dry place, away from light and out of the reach of children.