Dutasteride

Dutasteride is a prescription-only medicine that treats androgenetic hair loss (male and female pattern baldness) by blocking both type I and type II 5-alpha reductase, the enzyme that converts testosterone into DHT. It is used mainly in men, and in some women where a doctor judges it appropriate. Dutasteride is not licensed for hair loss anywhere in the UK, so it is prescribed as an unlicensed compounded medicine, and only after a doctor has assessed whether it is safe and suitable for you. At City Skin Clinic it is one of several actives a doctor may include in a topical treatment built around your hair loss.

What Is Dutasteride and How Does It Work?

Dutasteride works by blocking 5-alpha reductase, the enzyme that converts testosterone into dihydrotestosterone (DHT). DHT is the hormone that shrinks hair follicles in androgenetic alopecia, so hair grows back finer and shorter with each cycle until it stops. By lowering DHT at the scalp, Dutasteride can slow that shrinking and help follicles recover.

The difference from Finasteride is that Dutasteride blocks both type I and type II forms of the enzyme, where Finasteride mainly blocks type II. This is why it suppresses DHT more completely. The main benefits in a hair loss formula are:

• Reduces hair loss by lowering the DHT that drives follicle shrinking.
• Supports regrowth and density where follicles are miniaturised but not lost.
• Lower systemic exposure than the tablet when applied to the scalp, though not zero.
• Combines with other actives, so it can be built into a formula alongside Minoxidil and supporting ingredients.

How City Skin Clinic Uses Dutasteride

Every hair loss treatment we make is built around the individual patient’s hair loss, medical history and goals. Dutasteride is used mainly in men, and in some women where a doctor judges it appropriate. Your doctor decides the concentration, the base and whether Dutasteride works on its own or alongside other actives. We may include it in:

• Hair Loss Treatment for Men
• Hair Loss Treatment for Women

Dutasteride can be used on its own, but it is more commonly combined with other hair loss actives that support and complement its effect. The actives a doctor may use alongside it include:

• Minoxidil: the standard partner, this pairing can improve regrowth and density more than either active alone.
• Caffeine: stimulates the follicles and improves blood flow to the scalp.
• Melatonin: supports the hair growth cycle and helps protect follicles from oxidative stress.
• Tretinoin: a retinoid that may help other actives absorb.
• Hydrocortisone: can calm scalp irritation from other hair loss actives.

How Do You Get Topical Dutasteride in the UK?

In the UK, Dutasteride is a prescription-only medicine in both oral and topical form. The licensed capsules treat an enlarged prostate, not hair loss, and there is no licensed topical Dutasteride at all. So for hair loss it is prescribed as an unlicensed compounded medicine made individually by a specialist pharmacy. It cannot be bought over the counter, because it is a prescription-only medicine. It carries real risks and is not suitable for everyone. It is available for appropriate patients from some specialist clinics.

To access our hair loss treatments you first complete an online consultation form or book a virtual video consultation with one of our doctors. They design a treatment they judge will best address your hair loss, taking your wishes into account where it is safe to do so, then provide a plan and ongoing follow-up. You can email your doctor at any time as part of your treatment.

There is no subscription and no auto-renewal. Each course is a single order you place yourself.

Topical Dutasteride vs Finasteride

Dutasteride and Finasteride both treat androgenetic hair loss by lowering DHT, but Dutasteride blocks the enzyme more completely, which can make it more effective but also raises the potential for side effects. Dutasteride is reported to be roughly three times more potent than Finasteride at the type II enzyme and far more potent at type I, and it suppresses circulating DHT more completely.

Finasteride is the more established treatment for male pattern hair loss and may be better tolerated, so it is usually the first choice. Dutasteride is more often considered when Finasteride or other treatments have not worked. Although there is evidence that topical Dutasteride can increase hair growth with little change to DHT levels in the blood, studies are still small and more data is needed. What we do know is that applying either drug to the scalp lowers how much reaches the bloodstream compared with a tablet. However, it does not remove the risk of side effects.

How Effective Is Topical Dutasteride?

Oral Dutasteride has been used for years to treat an enlarged prostate, so its safety profile and side effects are well documented. As a topical hair loss treatment it is more promising than proven. Early trials show it can lower scalp DHT and improve hair count, but they are small, often short and frequently combine it with microneedling, and larger studies are still needed to establish how well and how safely it works on its own. It is prescribed as an unlicensed medicine, under a doctor’s care, and the benefits, risks and contraindications are worth discussing with your provider before starting.

What Strengths Does Topical Dutasteride Come In?

Because every formula is compounded from scratch, your doctor can prescribe topical Dutasteride across a range of strengths, usually somewhere between 0.001% and 0.25%. The right concentration depends on your hair loss, your medical history and the other actives in your formula.

Your doctor may choose the lower end of that range on purpose. This is because Dutasteride has a long half-life and stays in the body for weeks, so a lower scalp concentration lowers the chance of it building up while still working on DHT. A fixed off-the-shelf product offers one strength. A compounded formula lets the dose fit the person. No strength is risk-free, because absorption is never zero, but it does mean your doctor can aim for the lowest strength that works for you.

What Are the Side Effects of Topical Dutasteride?

Most people tolerate topical Dutasteride well, but it can cause side effects and you should know them before you start. Some of the side effects of Dutasteride include:

• Sexual side effects: reduced sex drive, difficulty getting or keeping an erection and problems with ejaculation. Applied to the scalp, less of the drug reaches the bloodstream than with the tablet, but that does not remove the risk.
• Mood changes: Dutasteride is in the same class of medicine as Finasteride. Following a review, the MHRA added a precautionary warning that mood alterations have been reported with this class. If you develop low mood, depression or thoughts of self-harm, stop and speak to your doctor.
• Breast changes: tenderness, discharge or enlargement of breast tissue (gynaecomastia). Report any new breast lump, pain or discharge to a doctor.
• PSA and prostate checks: Dutasteride can lower PSA, the blood marker used in prostate checks. This can make a reading look more reassuring than it really is. So tell any doctor checking your PSA that you use Dutasteride, whatever the form.
• Skin reactions at the scalp: irritation, itching or dryness where it is applied. In rare cases Dutasteride can cause a serious allergic reaction, such as a rash or swelling of the lips, tongue or throat. If that happens, stop using it and seek medical help.

Other effects can include testicular pain and dizziness. For most people the sexual side effects that do occur resolve after stopping the medicine. However, in a small number they can persist even after stopping the treatment, and because Dutasteride stays in the body for weeks that persistence matters more than it does with a short-acting drug. Your doctor should go through your history, assess your suitability and inform you of the risks. They should also provide proper aftercare.

Who Should Not Use Topical Dutasteride?

Topical Dutasteride is not right for everyone. Your doctor will not prescribe it if it is not safe or suitable, or if there are better options for you. In particular, it is not suitable for:

• A history of depression or anxiety: mood alterations have been reported with this class of medicine, so topical Dutasteride is not suitable for anyone with a history of depression, anxiety or suicidal thoughts.
• Women who are pregnant, could become pregnant or are breastfeeding: Dutasteride can harm a developing male baby, so it is not suitable for women who are pregnant, may become pregnant or are breastfeeding.
• Anyone living with someone who is pregnant, or couples trying to conceive: Dutasteride can be absorbed through skin contact, and pregnant women should avoid handling it or touching treated skin. A pregnancy can begin before anyone knows, so topical Dutasteride is not suitable if someone in your household is pregnant or if you and your partner are trying to conceive. Even where neither applies, let it dry fully, wash your hands after applying and keep the treated scalp away from young children.
• Scalp conditions: people with psoriasis or severe dermatitis at the scalp should avoid topical Dutasteride unless a doctor advises otherwise.
• Allergies: anyone with a known allergy or hypersensitivity to Dutasteride or any ingredient in the formula.
• Beards: Dutasteride is not suitable for beard growth. DHT drives beard growth, so blocking it would work against the goal.