Finasteride vs dutasteride for hair loss

In short: both lower DHT, the hormone behind male pattern baldness. Dutasteride blocks more DHT and may regrow a little more hair, but it stays in your body for months and is used off-label for hair in India. Finasteride has far more long-term hair data and is usually tried first. Both are prescription-only.

Side by side

	Finasteride 1 mg	Dutasteride 0.5 mg
Blocks	5-alpha reductase type II	Types I and II
Lowers blood DHT by	About two-thirds	Over 90%
Approved for hair loss	Yes (1 mg) in many countries	In some countries (e.g. South Korea, Japan); off-label elsewhere
Hair evidence	Strong, long-term (5+ years)	Good short-term trials; less long-term data
Regrowth	Good	Slightly more in head-to-head trials
Leaves the body after stopping	Within days	Takes months (half-life about 5 weeks)
Side effects	Small risk of sexual and mood effects	Similar type; possibly slightly more frequent
Form	Tablet	Soft capsule; also used as scalp injections (mesotherapy)
Cost per month (generic)	≈ ₹45–360	≈ ₹150–1,070

Which works better?

In a head-to-head trial, dutasteride 0.5 mg increased hair counts more than finasteride 1 mg over 24 weeks. Analyses comparing many treatments also rank dutasteride at or near the top.

But "works slightly better" isn't the only question. Finasteride has more long-term safety and hair data, and if side effects appear, it leaves your body quickly. That's why many dermatologists start with finasteride and consider dutasteride if the response isn't enough.

When dermatologists consider dutasteride

Finasteride hasn't worked well enough after about 12 months.
Hair loss is progressing quickly despite treatment.
After a hair transplant, to protect native hair (case by case).

Important differences for safety

It stays in the body much longer. If side effects appear, they may take longer to settle after stopping.
Blood donation: you need a much longer gap before donating than with finasteride. Check with the blood bank.
Pregnancy: women who are or could become pregnant must not handle leaking capsules.
PSA tests: both lower PSA readings. Tell your doctor before any prostate test.

Note: dutasteride combined with tamsulosin is a prostate medicine. It's not used for hair loss.

FAQs

Can I switch from finasteride to dutasteride? Only with your doctor. They'll weigh how well finasteride worked, any side effects, and your plans for children.

Are dutasteride injections (mesotherapy) better than tablets? They're used to reduce exposure throughout the body, but the evidence is still limited and technique varies by clinic.

Is dutasteride safe long-term? Long-term data comes mostly from older men taking it for the prostate. Data for young men using it for hair is more limited.

See a doctor soon if you have: round bald patches that appear suddenly · hair coming out in clumps · redness, pain, pus, scaling or scarring on the scalp · hair loss with fever, weight loss, irregular periods, acne or new facial hair · eyebrow or eyelash loss · hair loss in a child.

Sources

Gubelin Harcha W, et al. A randomized, active- and placebo-controlled study of the efficacy and safety of different doses of dutasteride versus placebo and finasteride in the treatment of male subjects with androgenetic alopecia. J Am Acad Dermatol. 2014;70:489–98.
Gupta AK, et al. JAMA Dermatol. 2022;158(3):266–74.
Dutasteride and finasteride prescribing information.

Medical review pending: not yet reviewed by a dermatologist. Medical disclaimer