Finasteride and Minoxidil Alongside a Hair Transplant: What the Studies Show

A hair transplant moves follicles from the back and sides of the scalp to areas that have thinned. It does not stop the hair loss process itself. Hair that was not transplanted can keep thinning in the years after surgery, which is why surgeons often talk to patients about medication before and after a transplant. The two most studied options are finasteride and minoxidil.

This article summarises what the clinical trials and official product information say. It is not a prescription. Whether either medicine suits you depends on a medical assessment.

Key facts

• In two one-year trials of 1,553 men aged 18 to 41, finasteride 1 mg increased hair count by 107 hairs in a 1-inch circle compared with placebo after one year, and by 138 hairs after two years.
• After 12 months, further hair loss was seen in 14% of men taking finasteride and 58% of men taking placebo, according to the US prescribing information.
• In a 48-week trial of 393 men, 5% topical minoxidil produced 45% more hair regrowth than 2% minoxidil.
• In May 2025 the European Medicines Agency confirmed suicidal thoughts as a side effect of finasteride tablets and added a patient card to 1 mg packs.
• In 2021, 69.1% of ISHRS members said they always or often recommend finasteride 1 mg.

Why medication matters after a transplant

Hair loss in men is usually progressive. A transplant can restore density in one area while the surrounding native hair continues to thin. Over time this can leave transplanted hair standing apart from thinning hair around it. Medication aims to slow or stop that ongoing loss, so the overall result stays more even.

The ISHRS Practice Census shows how common this approach is among hair restoration physicians:

Treatment	Members
Finasteride 1 mg	69.1%
Minoxidil solution (2% or 5%)	53%
Minoxidil foam 5%	53%
Platelet-rich plasma (PRP)	48.4%

Based on 157 responding members.

Source: ISHRS 2022 Practice Census

Finasteride: what the trials found

Finasteride blocks the enzyme 5-alpha reductase, which converts testosterone into dihydrotestosterone (DHT), a hormone involved in male pattern hair loss. The 1 mg tablet is approved for men with male pattern hair loss.

The key trials were published in 1998. They included 1,553 men aged 18 to 41. Hair was counted in a 1-inch (5.1 cm²) circle at the crown. Compared with placebo, men taking finasteride had 107 more hairs after one year and 138 more hairs after two years, while men on placebo continued to lose hair.

The US prescribing information also reports how men were assessed after 12 months:

Outcome	Finasteride 1 mg	Placebo
Further hair loss	14%	58%
Increased hair growth (investigator rating)	65%	37%
Increase on blinded photo assessment	48%	7%

Source: PROPECIA US prescribing information, clinical studies

Finasteride side effects

In the 12-month trials, sexual side effects were reported slightly more often with finasteride than with placebo. The product information states that these effects resolved in men who stopped treatment because of them. Post-marketing reports also describe sexual problems that continued after stopping the medicine.

Side effect	Finasteride 1 mg	Placebo
Reduced sex drive	1.8%	1.3%
Erectile problems	1.3%	0.7%
Ejaculation problems	1.2%	0.7%
Stopped treatment because of sexual side effects	1.2%	0.9%

Finasteride n = 945, placebo n = 934.

Source: PROPECIA US prescribing information, adverse reactions

In May 2025, after a review by its safety committee, the European Medicines Agency confirmed suicidal thoughts as a side effect of finasteride 1 mg and 5 mg tablets. How often it happens cannot be estimated from the available data. The agency concluded that the benefits still outweigh the risks, added a patient card to 1 mg packs and advised patients to stop the medicine and contact a doctor promptly if they notice mood changes. The review found no evidence linking suicidal thoughts to finasteride skin sprays.

The 1 mg tablet is not indicated for women. Women who are or may become pregnant should not handle crushed or broken tablets, because finasteride can affect the development of a male baby.

Topical finasteride

Topical finasteride is regulated differently from country to country. In the United States, no topical finasteride product is FDA-approved. In April 2025 the FDA warned about compounded topical finasteride after receiving 32 adverse event reports between 2019 and 2024, including sexual side effects, anxiety, depression and suicidal thoughts. It also noted the risk of exposing other people, particularly women, through contact with treated skin. In the European Union, finasteride skin sprays are authorised in some countries, and the EMA’s 2025 review found no evidence linking them to suicidal thoughts.

Minoxidil: what the trials found

Minoxidil is applied to the scalp as a solution or foam. In a 48-week randomised trial of 393 men aged 18 to 49, 5% minoxidil was more effective than 2% minoxidil and placebo, with 45% more hair regrowth than the 2% solution at week 48. Response also appeared earlier with the 5% solution. Itching and local irritation were more frequent with 5% minoxidil.

Some dermatologists also prescribe low-dose oral minoxidil off-label. This is a prescription decision with its own risks and monitoring, and it is not covered by the trials above.

Around the day of surgery

Surgeons often adjust medication around a transplant. Topical products, for example, may be paused while the scalp heals, because the skin is sensitive in the first days after surgery. The right timing depends on your procedure, so follow the written instructions your surgeon gives you rather than general advice online.

When to talk to a doctor first

• If you have a history of depression or mood problems, discuss finasteride carefully with a doctor before starting it.
• Women, particularly those who are or may become pregnant, should not use finasteride unless a doctor specifically advises it.
• If you have heart or blood pressure problems, ask a doctor before using minoxidil, especially in tablet form.
• Medication is optional. A transplant can still be planned for patients who decide not to use it, but the plan should allow for future hair loss.

During your consultation at Hair in Istanbul, your doctor reviews your hair loss pattern and medical history and explains which options are reasonable for you. Contact us for an online assessment.