Minoxidil, finasteride and other hair loss medicines — evidence and side effects

Key facts

• Minoxidil prolongs the hair growth phase
• Results usually take 3–6 months
• Finasteride reduces DHT in male pattern hair loss
• Women may use minoxidil and, in selected cases, anti-androgens
• Biotin can interfere with blood tests

Topical minoxidil

Topical minoxidil, available as a solution or foam, is used for androgenetic alopecia in both men and women. It works by prolonging the growth phase of hair and enlarging miniaturised follicles. It is applied to the dry scalp, usually once or twice daily depending on the strength and formulation. A temporary increase in shedding during the first weeks is common and often a sign that follicles are entering a new growth cycle. Visible results usually take three to six months, and benefits are maintained only while it is used. Possible side effects include scalp irritation, dandruff-like flaking and unwanted facial hair if the product runs onto the face.

Low-dose oral minoxidil

Low-dose oral minoxidil has become a widely used option for people who find topical products inconvenient or irritating. It is prescribed off-label at doses far lower than those once used for blood pressure. It may suit both men and women after assessment, but it is not suitable for everyone, particularly those with certain heart conditions or low blood pressure. Possible side effects include increased hair growth on the face or body, ankle swelling, light-headedness and a faster heartbeat. Dr. Abdullah Anis reviews your medical history and medicines, and may check blood pressure and arrange follow-up before and during treatment.

Finasteride and dutasteride for men

Finasteride reduces the conversion of testosterone to dihydrotestosterone, the hormone that drives follicle shrinkage in male pattern hair loss. Taken daily, it often slows or stops further loss and can improve density over months. Dutasteride works similarly and is sometimes considered when finasteride response is limited. A small proportion of men report side effects such as reduced libido or erectile changes, and mood changes have also been reported; these should be discussed openly before starting. Finasteride can affect PSA blood test results, so tell other doctors you are taking it. Women who are or could become pregnant must not take or handle crushed tablets.

Options for women

Treatment for female pattern hair loss often combines topical or oral minoxidil with addressing contributing factors such as iron deficiency or thyroid problems. In women with signs of excess androgens, such as acne, irregular periods or unwanted facial hair, anti-androgen medicines like spironolactone may be considered after assessment, with reliable contraception where needed, because they are not safe in pregnancy. Some women may be considered for finasteride in specific circumstances. Dr. Abdullah Anis tailors treatment to your age, health, family plans and hair loss pattern, and explains how and when to review progress.

Supplements, side effects and when to review

Supplements help mainly when there is a proven deficiency, such as low iron or vitamin D. High-dose biotin rarely helps people without deficiency and can interfere with laboratory tests, including thyroid and cardiac tests, so mention it before blood work. Avoid combining multiple online products without advice. Standardised photos every few months help judge response objectively. Contact the clinic if you develop chest pain, palpitations, significant swelling, breathing difficulty, breast lumps or tenderness, or persistent mood changes while on treatment. Stopping medication usually leads to gradual loss of the gains over months, so changes should be planned with your doctor.

Hair loss can come from genetics, hormones, iron or thyroid issues, stress, scalp inflammation or autoimmune alopecia. A dermatologist identifies the type before recommending treatment.

Prepared by the Manhal Medical Center editorial team · Updated: 2026-10-18 · Treating specialist: Dr. Abdullah Anis

This page is general information and does not replace a consultation. Suitability, risks and results vary between patients.