DHT Blockers for Hair Loss

DHT blockers are prescription medications and natural supplements that prevent dihydrotestosterone from binding to hair follicles. They are used to slow or stop male pattern baldness. Finasteride and dutasteride are the only clinically proven medical DHT blockers available in the UK.

Overview

• Dihydrotestosterone (DHT) is a male sex hormone responsible for the characteristics that make men appear masculine. DHT is responsible for a man’s deep voice, facial hair, muscle growth, and hair loss condition called male pattern baldness.
• Male pattern baldness is a genetic condition worsened by elevated DHT levels in the body. DHT overstimulates the hair follicles on the scalp, causing them to shrink and recede. Male pattern baldness can be treated using DHT blockers.
• DHT blockers (e.g. finasteride & dutasteride) prevent hair loss by reducing the amount of DHT that can bind to hair follicle receptors on your scalp. DHT hair loss medications have been clinically proven to slow hair loss in patients and improve hair growth.

What is a DHT Blocker?

DHT blockers are a medication designed to treat pattern hair loss conditions (androgenic alopecia). Unlike other hair loss treatments, they are scientifically proven to slow rates of male pattern baldness in patients, are cheap and easy to acquire, and are suitable for a wide range of patients.

A DHT blocker looks to block DHT from binding to receptors on your hair follicles, preventing hair loss symptoms like hair thinning, temple recession, and balding on the crown. By preventing hair loss, the life cycle of the hair follicle is extended, which helps promote hair growth. In turn, this leaves your hair looking thicker and fuller. It also hides previous signs of thinning/balding.

DHT-blocking medications come in several forms, from natural remedies to prescription treatments. The most common DHT blocker is a medication called finasteride. Finasteride is a common medication used to treat male pattern baldness. It is a safe and effective treatment you can purchase with a prescription from your GP.

DHT blockers are an effective treatment for patients suffering from mild to mid-stage hair loss (Stage 3-5 on the Hamilton-Norwood Scale). Medications like finasteride and dutasteride are also common prescription treatments for patients who have had hair transplants, as they help prolong the result of surgery.

What is DHT and its Effect on the Body?

DHT production is a vital part of your body’s hormonal regulation. Every day, your body converts testosterone into DHT. DHT is a more potent hormone than testosterone and performs a key role in the emergence and maintenance of male sex characteristics.

DHT is produced in the testes and circulates through your body using blood flow. Your body’s circulatory system enables DHT to reach almost everywhere in the body and bind to androgen receptors, including your scalp.

DHT is responsible for several roles in the body throughout puberty and adulthood. These include, but are not limited to:

• Muscle growth – DHT performs an important role in the production and maintenance of the body’s lean muscle mass.
• Hair Growth and Hair Loss – Perhaps paradoxically, DHT is also responsible for the increased growth of facial and body hair AND the increased rate of hair loss on the scalp.
• Increased libido (sex drive) – DHT is a potent male sex androgen. Elevated levels of DHT have been shown to increase sex drive in men.
• Prostate Growth – believe it or not, DHT blockers were originally designed to help reduce the size of the prostate in male patients. This is because elevated levels of DHT can cause an enlarged prostate.

The reason DHT causes hair loss on the scalp is due to the overstimulation of the hair follicles in this region. Due to the high concentration of 5 alpha-reductase receptors in this area, DHT amasses in the scalp and disrupts the growth phase (anagen) of the hair growth cycle.

DHT disrupts the hair growth cycles by making the initial growth phase (anagen) shorter than normal. This means your hair follicle has less time to grow before it falls out. Your hair doesn’t grow as long (or thick) as usual, giving the appearance of looking thinner.

Over time, DHT overstimulation causes hair follicle death. Your hair follicles miniaturise and stop producing hair altogether. For patients with male pattern baldness, this first affects the hairline (temples) before affecting the crown area.

Where hair follicles are spread more evenly around the body (such as the chest, armpits, face, etc), increased DHT production can increase hair growth. That’s why, during puberty, men will see an increased amount of hair growth in body and facial hair.

How Do DHT Blockers Work?

The science behind a DHT blocker is simple and fascinating! DHT blockers, or 5a-reductase inhibitors, prevent your body’s androgen receptors from binding to the male sex hormone Dihydrotestosterone (DHT). There are millions of 5 alpha-reductase receptors all over your body and a high concentration on your scalp.

DHT blockers prevent the hormone called DHT from binding to these receptors on the scalp, limiting the rate of overstimulation in scalp hair follicles. In turn, this helps slow down (and, in some cases, prevent) pattern hair loss development, keeping your hair looking thick and full.

A DHT blocker will not prevent your body from converting testosterone into DHT. It only prevents DHT from binding to your hair follicles. That is what makes it a safe and effective medical treatment with few side effects.

How Effective are DHT Blocking Medications?

DHT blockers are supported by a raft of scientific evidence, confirming their efficacy. Prescription treatments, like finasteride and dutasteride, are effective at reducing hair loss and increasing hair growth over 24 weeks.

In a study conducted by the Indian Journal of Dermatology (2014), results showed finasteride to be an effective DHT blocker in 60% of patients partaking in the study. Patients took a 1mg capsule of finasteride once a day, over 6 months. Evidence has also shown dutasteride to be equally, if not more effective at treating symptoms of male pattern baldness.

DHT-blocking medication is most effective in patients suffering from early to mid-stage hair loss. If you are suffering from severe hair loss (almost total scalp hair loss), the efficacy of finasteride is going to be limited. More drastic medical interventions, such as an FUE hair transplant, may be needed to restore your hair.

Medical DHT Blockers

DHT blockers have been around for decades now. They’re one of the most common medications prescribed to patients in the UK and US and are effective at treating hair loss, specifically male pattern baldness. But what are the most common DHT blockers available?

Finasteride

Without a doubt, finasteride is the most commonly prescribed DHT blocker for hair loss. Patented in 1984 and approved to treat hair loss in 1997, finasteride is the most common treatment prescribed to patients for androgenic alopecia.

Finasteride is a powerful DHT blocker used to treat early to mid-stage cases of male pattern hair loss. If you have social media, you’ll have seen numerous companies advertise finasteride. You can buy this prescription treatment over the counter or order it online!

Both finasteride and dutasteride come as oral medications in a 1mg dose. Patients usually take one tablet a day. It’s generally regarded as a quick, easy, and convenient to alternative hair loss treatment options like minoxidil or micro-needling.

What makes finasteride so popular is its low rates of side effects in patients (around 2%). Of this 2%, the most common side effect is erectile dysfunction, but this subsides with a smaller dose or time away from the treatment.

Dutasteride

Dutasteride is another prescription treatment for male pattern baldness. It is a more powerful treatment than finasteride as it has a longer half-life. This means dutasteride takes longer to break down in the body than finasteride.

In one scientific study, results showed dutasteride to be a more effective treatment than finasteride at treating hair loss. Dutasteride has also been shown to produce more consistent results across a broader range of patients.

That being said, results for finasteride are still impressive. If you’re interested in finasteride or dutasteride, be sure to book in for a free consultation, or speak with your GP.

Natural DHT Blockers and Herbal DHT Blockers

If you’re a little concerned about taking prescription medication for your male pattern baldness, there are several natural DHT blockers you can try to see if they are effective. Natural remedies for hair loss include, but are not limited to:

• Saw Palmetto – saw palmetto extract can help lower DHT levels in the body. In turn, this can help reduce hair loss and maintain hair density.
• Green Tea – green tea is renowned for its antioxidant properties. It contains catechins and Epigallocatechin Gallate (EGCG), which may reduce DHT levels in the body.
• Pumpkin Seed Oil – as well as reducing DHT levels in the body, pumpkin seed oil also possesses nutrients and vitamins that are vital for hair health. This treatment can be applied as an ointment or taken in capsule form.

While natural remedies are supported by anecdotal evidence, many lack scientific support and evidence from clinical trials. As with prescription treatments, consult your GP or hair loss doctor for the best plan of action!

DHT Blockers for Women

DHT blockers do not work the same way for women as they do for men, and understanding why is important before considering any treatment. In women, androgenetic alopecia is driven by a combination of genetic sensitivity to DHT and fluctuating oestrogen levels — not elevated DHT alone. This means that for many women, particularly those of pre-menopausal age, DHT is not the primary driver of hair loss, and blocking it may have limited effect while carrying meaningful hormonal risks.

Are DHT Blockers Safe for Women?

The standard medical DHT blockers: finasteride and dutasteride are not recommended for pre-menopausal women. Both are teratogenic, meaning they carry a risk of serious harm to a developing foetus, and for this reason they are contraindicated in women who are pregnant or may become pregnant. In the UK, neither is licensed as a hair loss treatment for women.

For post-menopausal women, the picture is different. With oestrogen levels significantly reduced after the menopause, DHT’s relative influence on hair follicles increases, making DHT-blocking medication more clinically relevant in this group. Some post-menopausal women are prescribed finasteride or dutasteride off-label by a specialist, though this remains uncommon and must be assessed on an individual basis by a GMC-registered clinician.

The DHT blocker most commonly considered for women is spironolactone, an anti-androgen medication originally used to treat high blood pressure and PCOS. Unlike finasteride, spironolactone works by blocking androgen receptors rather than inhibiting DHT production directly, and it has a more established safety profile in women. It is available on private prescription in the UK and is typically considered before finasteride or dutasteride for female pattern hair loss.

Can Natural DHT Blockers Help Women?

Natural supplements such as saw palmetto and pumpkin seed oil are sometimes used by women looking to avoid prescription medication. The evidence base for these in women is limited, but unlike finasteride and dutasteride, they carry no known hormonal contraindications at typical supplement doses. They are best considered a complementary measure rather than a standalone treatment.

For women experiencing hair loss, the most important first step is diagnosis, not treatment. Female hair loss has multiple causes beyond DHT sensitivity, including thyroid dysfunction, iron deficiency, telogen effluvium, and PCOS. Using a DHT blocker without establishing the cause risks wasting time and missing a treatable underlying condition. It is best to book a consultation with a dermatologist that has expertise in hair loss to assess the specific cause of your hair loss and advise on the most appropriate treatment pathway.

What is the Best DHT Blocker?

The honest answer is that there is no single best DHT blocker as the right choice depends on where you are in your hair loss journey, your tolerance for prescription medication, and whether your goal is to stabilise what you have or actively regrow.

For most men in the early to mid stages of pattern hair loss, finasteride is the appropriate starting point. It is the only DHT blocker licensed in the UK specifically for male pattern baldness. It reduces serum DHT levels by around 70% after six months of use and it has decades of clinical data behind it. For the majority of patients, finasteride is sufficient to halt further loss and, in some cases, produce modest regrowth.

Dutasteride is the stronger option as it inhibits both Type I and Type II 5-alpha-reductase enzymes, compared to finasteride’s Type II inhibition only, producing serum DHT reductions of up to 95%. Short-term studies (1&2) suggest dutasteride regrows hair faster and more densely than finasteride. However, it is not licensed in the UK for hair loss and is prescribed off-label, meaning it requires a private prescription from a specialist. It is typically considered for patients who have not responded adequately to finasteride, or those with more advanced androgenetic alopecia who want a more aggressive medical approach before considering a transplant.

Conclusion

Blocking DHT is vital if you’re looking to stop male pattern baldness in its tracks! The early stages of androgenetic alopecia can be treated using several DHT-blocking treatments. Patients can go down the natural or medical route. If you’re worried about your hair loss, book a free consultation today!