Can I get dutasteride in Japan if I am not Japanese?

Dutasteride is a prescription medicine in Japan, so you need a consultation with a doctor, who will decide whether it is appropriate for you. Both clinics in our group offer consultations in English.

Is dutasteride for hair loss covered by Japanese health insurance?

No. Zagallo and its generics are not listed on the national insurance drug price list. Insurance for Avolve, the BPH product, specifically excludes prescriptions for male pattern hair loss.

How long does it take to see results?

The Japanese package insert states that about six months of treatment is usually needed to evaluate the effect. Taking the capsule every day during that period matters.

Can I donate blood while taking dutasteride?

No. Japanese Red Cross guidance asks donors to wait six months after their last dose, and the FDA label also advises waiting at least six months. This is to avoid exposing a pregnant recipient to the drug.

Should I switch from finasteride to dutasteride?

Both drugs carry a grade A recommendation in the Japanese guideline. The clinic's own guidance notes that if finasteride or minoxidil is already giving satisfactory results, there is no particular need to switch. A doctor can review your progress with you.

Dutasteride in Japan: Approval, Prescription & English Care

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Skin & Dermatology, Guide for Foreigners in Tokyo
Dutasteride in Japan: Approval, Prescription & English Care

Skin & Dermatology Guide for Foreigners in Tokyo
2026.09.14

Dutasteride in Japan: Approval, Prescription & English Care

Dutasteride in Japan — hair loss capsule consultation at a Tokyo clinic

Dutasteride in Japan: Availability, Prescription and English-Speaking Clinics

Dutasteride in Japan: availability, prescription a — Dutasteride in Japan: Availability, Prescription and English

Finding hair-loss treatment in a new country is stressful, particularly when the medicine names, rules and pricing differ from what you know at home. If you have used dutasteride elsewhere, or are thinking of starting it in Tokyo, it helps to know how the drug is regulated in Japan before you book an appointment.

This guide explains how dutasteride is approved and prescribed in Japan, what the clinical evidence shows, what it costs in Tokyo, and where you can discuss it in English.

What you’ll learn in this article:

Which dutasteride products are approved in Japan, and for which conditions
How dutasteride works and what published studies report about results
How to get a prescription in Tokyo, and why personal import carries risks
Current self-pay prices at our clinic group, and who should avoid the drug
Where to get an English-language consultation in Tokyo

Have a question about this treatment?
Message us on LINE or WhatsApp — our English-speaking team usually replies the same day.

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What Is Dutasteride, and Is It Approved in Japan?

Dutasteride is an oral medicine that lowers levels of dihydrotestosterone (DHT), a male hormone that plays a central role in male pattern hair loss, known medically as androgenetic alopecia (AGA).

According to the Japanese Dermatological Association’s guideline, AGA affects around 30% of Japanese men overall. The same guideline reports rates of about 10% in men in their 20s, rising to over 40% from their 50s onwards.

In Japan, dutasteride is available under more than one approval, and the distinction matters.

Avolve (0.5 mg) has been used in Japan since September 2009 for benign prostatic hyperplasia (BPH), a non-cancerous enlargement of the prostate.
Zagallo (0.1 mg and 0.5 mg capsules) received Japanese marketing approval on 28 September 2015, specifically for male pattern hair loss in men.
Generic dutasteride for hair loss followed, with the first approvals granted in October 2020 as generics of Zagallo 0.5 mg.

Product	Approved use in Japan	Strengths	Insurance cover for hair loss
Zagallo (brand)	Male pattern hair loss in men	0.1 mg, 0.5 mg	No (self-pay)
Generic dutasteride “ZA”	Male pattern hair loss in men	0.5 mg	No (self-pay)
Avolve (brand)	Benign prostatic hyperplasia	0.5 mg	No: insurance is explicitly excluded when prescribed for hair loss

In the United States, the situation is different. The US Food and Drug Administration (FDA) label for Avodart covers only symptomatic BPH, so dutasteride is not FDA-approved for hair loss. In Japan, by contrast, dutasteride holds a formal approval for male pattern hair loss.

How Dutasteride Works and What Results to Expect

Testosterone is converted into the more potent DHT by an enzyme called 5-alpha-reductase, which exists in two forms (type I and type II). In hair follicles on the scalp, DHT shortens the growth phase, so hairs become progressively thinner and shorter.

Finasteride blocks only the type II enzyme. Dutasteride blocks both type I and type II, which is why it is described as a “dual” inhibitor. It also stays in the body for a long time: the FDA label gives a terminal half-life of about five weeks at steady state, and blood levels can remain detectable for four to six months after stopping.

What the evidence shows

The Japanese Dermatological Association’s 2017 guideline, still the current published version, gives oral dutasteride its highest recommendation (grade A) for male pattern hair loss. It rates the drug grade D, meaning it should not be used, for female pattern hair loss.

A systematic review cited in the guideline analysed 16 randomised trials involving 4,950 men. For improvement on scalp photographs, dutasteride 0.5 mg/day outperformed placebo with an odds ratio of 16.38.
In an international trial of 917 men aged 20 to 50, dutasteride 0.5 mg/day significantly increased hair count and hair width at 24 weeks compared with finasteride 1 mg/day (P = .003 for hair count) and placebo. Adverse events were similar across groups.
In a 52-week Japanese study of 120 men taking 0.5 mg/day, clinical reports indicate the density of non-vellus hairs rose by 13.5 per cm² and terminal hairs by 15.2 per cm².

Results take time. The Japanese package insert states that about six months of treatment is usually needed to judge whether the medicine is working. Dutasteride controls AGA rather than curing it, and the guideline notes that trials did not examine efficacy beyond one year or hair changes after stopping.

Dutasteride is often combined with a topical treatment. Topical minoxidil also carries a grade A recommendation in the Japanese guideline. It is available at BIOTOPE CLINIC in Shirokanedai, so feel free to ask about it during a consultation with Dr. Karibe.

Real Patient AGA Treatment Results — Before & After

The following are actual AGA (androgenetic alopecia) treatment results from patients at Kojimachi Dermatology & Plastic Surgery Clinic and its sister clinic BIOTOPE CLINIC (Shirokanedai, Minato-ku, Tokyo), both directed by Dr. Jun Karibe. Photos are shared with patient permission. Individual results vary depending on age, hair loss stage, adherence to medication, and treatment plan. Tap each case to view the full treatment disclosure required by the Japanese Medical Advertising Guidelines.

AGA before and after — male pattern hair loss treatment result Tokyo — Case 1 — Before & After (tap for details)

AGA finasteride result — Kojimachi Dermatology Clinic Tokyo case photo — Case 2 — Before & After (tap for details)

AGA dutasteride treatment before and after — English-speaking Tokyo clinic — Case 3 — Before & After (tap for details)

AGA minoxidil hair regrowth result — Tokyo dermatology case study — Case 4 — Before & After (tap for details)

AGA combination therapy result — Dr. Jun Karibe, board-certified plastic surgeon — Case 5 — Before & After (tap for details)

Androgenetic alopecia treatment before/after — BIOTOPE Clinic Shirokanedai — Case 6 — Before & After (tap for details)

AGA hair mesotherapy result — Tokyo scalp regenerative treatment case — Case 7 — Before & After (tap for details)

AGA scalp coverage improvement — Kojimachi Clinic, English care — Case 8 — Before & After (tap for details)

AGA patient case — Tokyo cosmetic dermatology, board-certified physician — Case 9 — Before & After (tap for details)

Hair loss treatment result Tokyo — Dr. Karibe, English-speaking AGA clinic — Case 10 — Before & After (tap for details)

Getting a Prescription in Tokyo: Before, During and After

All dutasteride products in Japan are prescription medicines, so you need a consultation with a doctor. There is no downtime, because it is a daily capsule, but a few practical points are worth knowing.

Before your consultation

Bring details of any hair-loss medicine you have taken abroad, including the product name, dose and how long you took it.
Mention any liver disease. Severe hepatic impairment is a contraindication, meaning the drug should not be used.
Tell the doctor if you have had recent PSA (prostate-specific antigen) blood tests or are due for prostate screening.

During treatment

The standard starting dose for Zagallo is 0.1 mg once daily, which can be increased to 0.5 mg once daily if needed.
Swallow capsules whole. Do not chew or open them.
Dutasteride lowers PSA by roughly 50%. Japanese guidance advises doubling the measured value when comparing it with normal ranges, so always tell any doctor checking your PSA that you take it.
Do not donate blood. Japanese Red Cross guidance defers donation until six months after stopping dutasteride, compared with one month for finasteride.

Why personal import is risky

Japanese rules allow individuals to import prescription medicines for their own use without prior confirmation only up to one month's supply, based on the labelled dosage. The Ministry of Health, Labour and Welfare's regional bureau warns that products sold as medicines may include counterfeits or substandard items that are difficult for the public to identify. A domestically approved product prescribed after a medical consultation avoids that uncertainty.

Where to get dutasteride in Tokyo

Within our clinic group, both BIOTOPE CLINIC (Shirokanedai, Minato-ku) and Kojimachi Dermatology & Plastic Surgery Clinic (Ichigaya, Chiyoda-ku) offer English-language consultation with Dr. Jun Karibe's team. Dutasteride for male pattern hair loss is handled at BIOTOPE CLINIC, the group's cosmetic and men's health branch. Bookings and enquiries in English: LINE or WhatsApp.

Cost in Tokyo

AGA treatment in Japan is self-pay (jihi), so the full cost is paid by the patient. The following tax-inclusive prices appear on the clinic group's public price pages as of September 2026:

Consultation fee (initial or follow-up): ¥3,300. A consultation with Dr. Karibe is listed at ¥5,500.
Generic dutasteride: ¥7,700 per prescription. Please confirm the quantity supplied at your consultation.
Zagallo (brand dutasteride), box of 30: ¥11,000
Finasteride, box of 28 (for comparison): ¥5,280
Topical minoxidil 5%: ¥5,500

Prices can change, so please check the clinic's official price page or contact us for a current quote. For an accurate quote, please book a consultation.

Have a question about this treatment?
Message us on LINE or WhatsApp — our English-speaking team usually replies the same day.

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Who Is a Good Candidate, and Who Should Avoid It?

Dutasteride may suit adult men with a diagnosis of male pattern hair loss who want an oral treatment with strong guideline support. It may also suit men who have not had a satisfactory response to finasteride. A doctor will first rule out other causes of hair loss.

Who should not take it

Women: contraindicated. Because lowering DHT may affect the normal development of a male foetus, women, especially those who are pregnant or may become pregnant, should not touch capsules that are leaking.
Children and under-20s: contraindicated in children, and safety in people under 20 has not been established in Japan.
People with severe liver impairment or a known allergy to dutasteride.

Side effects to discuss

Sexual side effects are the most common concern. In the international trial cited by the Japanese guideline, reduced libido occurred in 3.3% of men, erectile dysfunction in 5.4% and ejaculation disorder in 3.3%. The 52-week Japanese study reported higher rates of 8.3%, 11.7% and 5.0% respectively. Breast enlargement and liver dysfunction are also listed in the package insert.

BIOTOPE CLINIC's men's health service also covers erectile dysfunction treatment, so you can raise any concerns about sexual function during a consultation with Dr. Karibe.

Common Misconceptions About Dutasteride

"It is FDA-approved for hair loss, so the rules are the same everywhere"

This is not correct. The FDA label covers BPH only, whereas Japan approved dutasteride specifically for male pattern hair loss in 2015. Prescribing practice and product strengths therefore differ between countries.

"Dutasteride is dramatically stronger than finasteride"

The evidence is more nuanced than that. The Japanese guideline notes that in the 917-man trial, dutasteride was better for total hair count and hair diameter, but there was no significant difference in the number of thick terminal hairs (60 µm or more). Differences in expert photo scores were small, at 0.14 points for the crown and 0.24 for the front. The guideline concludes that the difference between the two drugs needs further study.

Frequently Asked Questions

Q. Can I get dutasteride in Japan if I am not Japanese?: Dutasteride is a prescription medicine in Japan, so you need a consultation with a doctor, who will decide whether it is appropriate for you. Both clinics in our group offer consultations in English.
Q. Is dutasteride for hair loss covered by Japanese health insurance?: No. Zagallo and its generics are not listed on the national insurance drug price list. Insurance for Avolve, the BPH product, specifically excludes prescriptions for male pattern hair loss.
Q. How long does it take to see results?: The Japanese package insert states that about six months of treatment is usually needed to evaluate the effect. Taking the capsule every day during that period matters.
Q. Can I donate blood while taking dutasteride?: No. Japanese Red Cross guidance asks donors to wait six months after their last dose, and the FDA label also advises waiting at least six months. This is to avoid exposing a pregnant recipient to the drug.
Q. Should I switch from finasteride to dutasteride?: Both drugs carry a grade A recommendation in the Japanese guideline. The clinic's own guidance notes that if finasteride or minoxidil is already giving satisfactory results, there is no particular need to switch. A doctor can review your progress with you.

Have a question about this treatment?
Message us on LINE or WhatsApp — our English-speaking team usually replies the same day.

Book via LINE
Message on WhatsApp

Summary

Dutasteride is formally approved in Japan for male pattern hair loss, both as the brand Zagallo and as generics, and it is recommended at the highest grade in the Japanese guideline. It requires a prescription, is not covered by insurance for hair loss, and takes around six months to show whether it is working. Women must avoid it, blood donation is deferred for six months after stopping, and PSA results need adjusting while you take it.

If you have questions about dutasteride, both BIOTOPE CLINIC (Shirokanedai, Minato-ku) and Kojimachi Dermatology & Plastic Surgery Clinic (Ichigaya, Chiyoda-ku) offer English-language consultation with Dr. Karibe and his team. Dutasteride treatment for hair loss is primarily handled at BIOTOPE CLINIC. English enquiries: LINE or WhatsApp.

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References

Manabe M, Tsuboi R, Itami S, et al.; Guideline Committee for Male and Female Pattern Hair Loss. Guidelines for the diagnosis and treatment of male-pattern and female-pattern hair loss, 2017 version. Japanese Journal of Dermatology (Nippon Hifuka Gakkai Zasshi). 2017;127(13):2763-2777.
Gubelin Harcha W, Barboza Martínez J, Tsai TF, 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. Journal of the American Academy of Dermatology. 2014;70(3):489-498.e3.
GSK. Zagallo Capsules 0.1 mg / 0.5 mg (dutasteride), Japanese package insert.
GlaxoSmithKline. AVODART (dutasteride) soft gelatin capsules, US prescribing information. Revised October 2023.
Kanto-Shinetsu Regional Bureau of Health and Welfare, Ministry of Health, Labour and Welfare. On the importation of pharmaceuticals and related products (Iyakuhin-to no yunyu ni tsuite).

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