Topical Dutasteride Guide: Uses, Results & Side Effects

Reading time: 6 min.

Medically reviewed by
Dr. Michael May (FRCS) — Updated on December 29, 2025

Dutasteride is one of the most effective non-surgical hair loss treatments for male pattern baldness [1]. As a 5-alpha reductase inhibitor, it blocks the production of the hormone responsible for male pattern hair loss, dihydrotestosterone, or DHT.

Topical Dutasteride is currently undergoing clinical trials as an alternative to the traditional oral drug for treating androgenetic alopecia in men [1]. So what do we know about topical Dutasteride as a hair loss treatment so far?

Here, we’ll explore:

If and how topical Dutasteride works
Before and after photos of topical Dutasteride users
The potential side effects of topical Dutasteride.

Table of Contents

What is Dutasteride and how does it work for hair loss?
Does topical Dutasteride work?
Why is micro-needling used to apply topical Dutasteride?
Topical Dutasteride before and after
Topical Dutasteride side effects
How to apply topical Dutasteride
How to get topical Dutasteride

What is Dutasteride and how does it work for hair loss?

Dutasteride is a medication used to treat benign prostatic hyperplasia (BPH) as well as hair loss. Oral Dutasteride works by preventing the 5-alpha reductase (5-AR) enzyme in your body from converting testosterone to DHT. This leads to lower levels of DHT throughout the body, so the hormone is less likely to bind to androgen receptors in your hair follicles and cause them to shrink.

This is the same process behind oral Finasteride, though Dutasteride is generally said to be more effective as it inhibits all three types of 5-AR, while Finasteride only reduces the impact of two [1]. Multiple studies have shown that topical Finasteride also works, by reducing DHT levels in the area it’s applied (namely, the scalp) while also creating fewer systemic side effects [2-3]. So can topical Dutasteride have a similar effect?

Does topical Dutasteride work?

Early research on the effectiveness of topical Dutasteride is limited but promising. Topical Dutasteride is currently undergoing phase 2 clinical trials in the US to establish its safety and effectiveness for men with male pattern baldness [4]. The study is planned for completion in April 2024.

In the meantime, a handful of smaller studies have found some encouraging data to suggest that topical Dutasteride does work for androgenetic alopecia (pattern hair loss).

One study explored the effectiveness of using topical Dutasteride alongside micro-needling to promote hair growth [5]. 53% of participants using topical Dutasteride had a marked improvement in hair growth after 4-5 months, compared with just 18% of those using a saline solution (both groups also used micro-needling). Marked improvement was defined as improving by one full level on the Norwood Scale.

In addition, patients using topical Dutasteride had slight improvements in hair thickness and density. This suggests that topical Dutasteride is more effective for hair loss than micro-needling alone.

Another study found that combining topical Dutasteride with topical Finasteride and Minoxidil significantly improved hair growth in 90 days [6]. This could be reduced more quickly by supplementing treatment with Propecia and ketoconazole shampoo. In fact, aggressive treatment with all these medications could result in significant hair growth in just 30 days.

Due to the combination of active ingredients, it’s difficult to establish the exact contribution of topical Dutasteride for these patients. But it suggests it can at least play a supplementary role in hair regrowth.

Topical Dutasteride effectiveness: study details

Phase 2 clinical trials are testing the effectiveness of 0.15% w/w topical Dutasteride over 7 months [4]. The study includes 45 men aged 18 or over who are not currently undergoing hair loss treatments and have not undergone any in the last three months.

The microneedling study involved using a 2.5mm penetration depth microneedle across the affected areas before applying a 0.01% topical Dutasteride solution [5]. Patients were advised not to shampoo their hair for 12 hours after treatment. This study included 37 men aged 18-65 who were randomised to receive the topical Dutasteride or saline solution alongside microneedling.

The final study tests a novel topical combination of Finasteride, Dutasteride, and Minoxidil, which is blended in a hypoallergenic lotion [6]. It also compared the effectiveness of this lotion with other treatments, including ketoconazole shampoo, oral Finasteride, and Rogaine foam. The study included 15 male participants, all of whom saw significant hair regrowth within 90 days of treatment.

Why is micro-needling used to apply topical Dutasteride?

Microneedling, also known as derma rolling, is a treatment that uses tiny sterilised needles to prick the skin, stimulating collagen production and promoting hair growth.

Dutasteride is a large molecule, so it’s more difficult to penetrate the skin without intervention. Micro-needling is often used in conjunction with topical Dutasteride to help the active ingredient penetrate the skin more easily.

Topical Dutasteride before and after

These patients show the impact of using topical Dutasteride for treating hair loss:

Topical Dutasteride side effects

The side effects noted from the limited studies into topical Dutasteride include:

Headaches
Itchiness
Pain

These side effects were reported in a study that also used microneedling [7]. So it’s unclear which aspect of treatment has caused these side effects.

Other side effects you may experience include:

Flakiness and dryness
Scaling
Hair colour or texture changes
Skin irritation
Increased sun sensitivity

Even if you experience any of these, Dutasteride side effects aren’t permanent in most cases. They tend to subside within the first year of use.

Recommended

Can Women Take Dutasteride?

Does topical Dutasteride go systemic?

One of the main arguments for using topical Dutasteride is to avoid the systemic side effects of 5-alpha reductase inhibitors, such as erectile dysfunction and low libido.

However, some people worry that Dutasteride administered in its topical form can eventually lead to systemic side effects. There’s no research yet to establish whether this is the case.

We can make a few educated guesses, though, based on the features of Dutasteride and the more extensive research for topical Finasteride. This suggests that topical Finasteride is a good way to get hair regrowth benefits without the systemic side effects [2].

In addition, because Dutasteride is a large molecule, it doesn’t penetrate the skin easily. Researchers have attempted to improve absorption by creating different delivery methods of Dutasteride, such as nanoparticles and liposomes [8]. The need for these studies suggests it’s unlikely that topical Dutasteride will reach high enough systemic levels to cause side effects.

It’s also important to note that serious side effects are extremely rare with both Finasteride and Dutasteride [9-10]. So using a topical formulation may help lower the risk even further.

How to apply topical Dutasteride

Topical Dutasteride usually comes in a dropper bottle, so it’s easy to apply. Here’s what you need to do:

Wash and dry your hair — application is easiest and most effective if the area is clean and dry.
Apply the prescribed amount using the dropper — don’t exceed the amount recommended by your doctor or trichologist.
Spread solution across the balding areas — use your fingers to move the solution across the affected area (but don’t rub it in).
Repeat as prescribed — repeat these steps as recommended by your doctor or trichologist.

As current studies show topical Dutasteride to be effective alongside micro-needling treatment, this can also form part of your application process. Micro-needling can increase the ability of the Dutasteride solution to penetrate the skin [9].

Anecdotal evidence suggests micro-needling and topical Dutasteride application frequency needs to happen more than once every ten days to create visible results.

How to get topical Dutasteride

Topical Dutasteride is still in clinical trials, so it’s not yet widely available. However, a trichologist may be able to prescribe it to you as an off-label male hair loss treatment.

To find out if topical Dutasteride is a suitable hair loss treatment for you, book a free consultation at the Wimpole Clinic. We can find and prescribe the right treatment to help you manage your hair loss.