In the UK, dutasteride is licensed as a treatment for an enlarged prostate. But it’s sometimes used off-label for hair loss.
So, how does dutasteride work—and could it help with your hair? Read on to find out.
Key Takeaways
- Mechanism of action: Inhibits the enzyme 5-alpha reductase to lower levels of DHT
- Efficacy: 80.3-92.4% effective
- UK availability: Private prescription
- Side effects: Similar to finasteride – Lower libido, erectile dysfunction, gynaecomastia, rarely mood disorders
- Safety profile: Generally well-tolerated
What is dutasteride?
It’s a type of medicine called a 5-alpha reductase inhibitor. That means it blocks (inhibits) the actions of the enzyme 5-alpha reductase.
In the UK, dutasteride is sold under the brand name Avodart.
How dutasteride works: mechanism of action
By blocking the actions of 5-alpha reductase, dutasteride prevents it from converting testosterone into another, more potent hormone called dihydrotestosterone (aka DHT).
DHT makes the hair follicles on your scalp get smaller over time. As this happens, your hair gets thinner and lighter in colour until the follicles completely shrink—and hair stops growing. So, with less DHT, you may be able to prevent hair loss.
Dutasteride results: how effective is it?
Research shows that dutasteride works well in treating hair loss. Depending on the hair loss pattern, one analysis found it to be effective for 80.3-92.4% of people taking it. Plus, 38 out of 42 participants in another study (90%) saw an improvement after taking dutasteride for at least a year.
In a phase III clinical trial of 139 men, the group taking dutasteride saw a significant increase in hair count compared to those taking placebo. They also saw greater improvements in hair growth.
Another study of 31 men found that hair density and thickness increased by 10.3% and 18.9% respectively after taking dutasteride for at least six months.
How long does dutasteride take to work?
Some men see results within a few months: in clinical studies, significant hair growth has been observed by the 12-week mark. It typically takes about 3-6 months to start noticing changes.
Dutasteride side effects
Dutasteride can cause side effects but not everyone will get them. Some symptoms that have come up in clinical research are:
- Decreased libido
- Erectile dysfunction
- Gynaecomastia (breast tissue growth)
- Mood disorders
Generally speaking, dutasteride is reported to be well-tolerated.
Do dutasteride side effects go away?
Normally, yes, your side effects will clear up as your body gets used to the medication. Everyone’s different, so we can’t say for sure how long it will take. But for some people, symptoms resolve within a matter of weeks or months.
If you decide to stop dutasteride, remember it takes around 5 weeks for it to start leaving your system. So, some symptoms might persist for a bit after you stop taking it. Speak to your provider if they don’t go away.
Dutasteride dosage and forms for hair loss
The most common way to take dutasteride is as a daily tablet, at a dose of 0.5mg.
But you can also get topical dutasteride for hair loss. It’s a promising new treatment that you spray directly onto your scalp. In a phase II clinical trial, 0.05% dutasteride solution outperformed oral finasteride (one of the main treatments for hair loss), showing larger increases in hair count.
Topical dutasteride is not a licensed product in the UK. It is usually prepared as a custom (compounded) medicine, so only use reputable services with a UK prescriber and a GPhC-registered pharmacy.
At Manual, we currently offer oral capsules that combine dutasteride with minoxidil. We do not offer topical dutasteride at this time while we continue to assess the evidence.
Dutasteride vs finasteride
Finasteride is another 5-alpha reductase inhibitor that’s used for hair loss in men. Here’s how these two medicines compare.
Is dutasteride better than finasteride?
Dutasteride has been shown to drive bigger increases in hair count and thickness compared to finasteride.
But that doesn’t mean that dutasteride is the best option for you personally. Everyone responds differently to medicine and your provider will help you find what’s best.
How to get dutasteride in the UK
If you want to try dutasteride for hair loss, you’ll have to get it via private prescription. You could try a private clinic or registered online pharmacy.
Head’s up: make sure your provider is qualified and registered. This information should be on their website.
At MANUAL, our team of clinicians can help you find the right hair loss treatment. Take our quiz to get started.
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