Topical finasteride spray: the trial, and how it compares with the tablet

Finasteride for hair loss is usually a tablet. The appeal of a scalp spray is easy to state: the same medicine, applied where the hair grows, with less of it reaching the rest of the body. The hope is the tablet's benefit with fewer side effects.

In the sources we reviewed, one spray has been tested against a placebo, in one trial that lasted 24 weeks. It raised hair count, and less finasteride reached the blood than with the tablet. Whether that means fewer side effects has not been established. This page sets out what the trial measured, what one product label says about use, and why "topical finasteride" is not the same thing in every country.

What topical finasteride is

Topical means applied to the skin. Three different things go by the name, and the evidence for one does not carry over to the others. ^{[1, 2, 3, 4, 5, 6]}

The first of the three is the one with a placebo-controlled trial, so most of this page is about it. Its strength is written as 2.275 mg per mL, or 0.25% by weight. A percentage alone does not identify a product. The studied spray delivers 0.05 to 0.2 mL a day, so a liquid of the same percentage used at 1 mL a day is 5 to 20 times that volume. ^[1]

This page is about adult men with male pattern hair loss: gradual thinning at the hairline or the crown. Sudden shedding, patches and a sore scalp are different problems, set out in types of hair loss in men. The tablet, which is the form with the long trials and the US and UK labels, is covered in the full finasteride profile.

What the spray trial found

The spray's main evidence is one placebo-controlled trial of one product. It randomly assigned 458 men aged 18 to 40, with mild to moderate thinning at the crown, to three groups: the finasteride spray, the same spray without finasteride, or a 1 mg finasteride tablet. Every man used a spray and took a tablet, with dummy versions making up the difference, so nobody knew which treatment he was on. A study doctor chose the number of sprays, from one to four, according to the size of the thinning area. Treatment lasted 24 weeks. ^[1]

Of the 458 men, 323 completed the trial. Hairs were counted on close-up photographs of a 1 cm² patch at the crown, marked with a tattoo so that the same spot was photographed each time. Photographs good enough to count, at the start and during treatment, existed for 250 men. ^[1] Where this and other trials counted hair, and what that leaves for the front of the scalp, is covered on the page about a receding hairline.

The spray did better than the spray without finasteride, and the difference was already there at 12 weeks. The trial's entry in the EU clinical trials register reports the size of the gap at 24 weeks with its margin of error: 13.6 more hairs per cm² with the finasteride spray, in the 202 men of those two groups who had usable photographs. ^{[1, 7]}

How much weight the result can carry

Spray and tablet side by side

The tablet group was in the trial as a reference. After 24 weeks the hair count had risen by 20.2 per cm² with the spray and by 21.1 with the tablet. Close numbers are not proof of equal effect. The comparison with the tablet was descriptive: the trial was designed to test the spray against a spray without finasteride, not to test whether spray and tablet are equivalent. The tablet group was also small: 84 men were followed for side effects, and 48 had usable photographs. ^[1]

For what the tablet's own trials measured, over one year and then five, see what the tablet trials measured in the profile.

What reaches the blood

Finasteride lowers the level of a hormone called DHT in the blood. In the spray trial, the amount of finasteride measured in the blood was much lower with the spray than with the tablet. DHT still fell in both groups. ^[1]

Side effects recorded with the spray

Side effects were recorded in 446 men: 181 on the finasteride spray, 181 on the spray without finasteride and 84 on the tablet. Treatment lasted 24 weeks, with safety visits up to week 28. ^{[1, 8]}

The trial also counted the men who stopped treatment because of a side effect.

The paper as first published placed the 7.1% in the spray group. A correction published afterwards assigns it to the tablet group, with 2.8% for the spray and 2.2% for the spray without finasteride. The correction did not change the hair-count results. Its wording still calls these withdrawals treatment-related, while the paper's table lists them under any side effect, so we show both rows as the table has them. ^{[1, 8]}

Regulators treat the two forms separately. The European review that in 2025 confirmed suicidal thoughts as a side effect of finasteride tablets found no evidence linking them to the sprays. That is an absence of evidence in that review, not a guarantee. The UK regulator's 2026 notice on depression, suicidal thoughts and sexual problems that can continue after stopping is about the tablets. It should not be read across to the sprays, in either direction. ^{[12, 13]}

How the Spanish label says to use it

A product label is the reference for how much to use and how often, and it belongs to one product in one country. The label we read is the Spanish one for Alocare 2.275 mg/mL, in the text revised in February 2022, checked on 30 September 2026. The table sets it next to what the trial did. ^{[2, 1]}

The chart below puts the spray's timing next to the tablet's.

Compounded sprays in the United States

In the United States no finasteride product for the scalp is approved, on its own or mixed with anything else. What is sold there is made to order by compounding pharmacies. ^[3]

A large set of numbers on products of this kind comes from a US telehealth company, which analysed its own records from April 2021 to April 2025. The three products it describes all contain finasteride 0.3% with minoxidil: a spray and a serum with minoxidil 6%, and a spray with minoxidil 7% plus ketoconazole and biotin. None of them is the 2.275 mg/mL spray from the trial. ^[4]

The reactions men wrote in about included scalp irritation, dizziness, a faster heartbeat, sexual problems and depression. About three quarters of the men did not answer the follow-up, the answers are the patients' own, and side effects were not tracked in a structured way. The report describes what those men said. It cannot show that a scalp product is safer than the tablet, and it does not cancel the FDA's alert. ^{[4, 3]}

Finasteride and minoxidil in one scalp product

The three products in the telehealth report all combine finasteride with minoxidil. Five small trials have tested the two medicines together on the scalp, as one liquid or as two products. Their results do not agree. ^{[5, 6, 17, 18, 19]}

A trial that finds no significant difference has not proved that the mix adds nothing, and a favourable result belongs to the preparation that was tested. In what we could read, none of these trials reported side effects thoroughly enough to compare safety. Funding was declared as none in the 60-man trial. The 12-week trial was supported by a research grant from L'Oréal, PERDOSKI and Universitas Indonesia, declared to have had no role in the study. For the other three it was not identified in what we could read. One more report, of 164 men over 12 weeks, describes its groups and its totals inconsistently, so we take no result from it. ^[20]

Product labels are more restrictive. The Spanish spray label says not to apply other products to the treated area, and the two UK minoxidil labels restrict use with other medicines applied to the scalp. ^{[2, 21, 22]} The numbers behind each of these trials are in minoxidil and finasteride together, and the wider question of what to combine is in hair loss routines.

Where you can get it, and what it costs

Approval depends on the country and on the exact product. This is what our sources record. It is not a complete map. ^{[2, 14, 15, 12, 3]}

We found no price for the spray on its own. The one offer we saw in the UK, on 29 September 2026, was a made-to-order mix of finasteride 0.3%, minoxidil 5% and tretinoin 0.01% at £26 for 60 mL, which the provider's instructions would use up in 30 days, plus £2.90 delivery. That is a different product, and its price cannot stand for the spray. In the same check, 30 days of finasteride tablets cost $26.67 in a US example and £9.46 in a UK example, as set out under what finasteride costs.

Where the spray sits in our comparison

Finasteride is second in our ranking of six ingredients, in the top tier it shares with minoxidil. That place rests on the 1 mg tablet. The spray does not inherit it. We assess the spray separately, as a conditional option: one that becomes relevant when a specific question applies, such as wanting to discuss an alternative to the tablet with a prescriber in a country where the spray is authorised.

How the eight criteria work is explained under how we rank and on the methodology page. The tablet's own assessment, with its risks, is in the profile.

What is not known

Where to go next

Topical finasteride and topical dutasteride are separate questions. Our dutasteride page explains its own experimental formulation rather than transferring the finasteride findings.

The spray is one form of one medicine. The pages below cover the rest of the decision: the tablet, its side effects, and how finasteride compares with the other options for male pattern hair loss. The six ingredients are set side by side in the comparison in the main guide.