Male pattern baldness: causes, treatments and what the evidence says

The British Association of Dermatologists calls male pattern hair loss the most common type of hair loss in men, and says it can affect men of any age. Alopecia UK says around half of men over 50 are affected, although it can also start in younger adults and occasionally in the early teens.

The NHS places male and female pattern baldness among the types of hair loss that are permanent and usually run in the family, in contrast to temporary hair loss from illness, stress, cancer treatment, weight loss or iron deficiency. That distinction matters, because temporary shedding needs a different approach.

Alopecia UK explains that testosterone is converted to dihydrotestosterone, and that this androgen causes the balding process. The hair follicle shrinks in a process called miniaturisation, so each hair that grows is shorter and thinner than the last.

The British Association of Dermatologists says it is believed to be inherited from either or both parents, and that over 190 genes have been identified as contributing, which helps explain why relatives can be affected to different degrees and at different ages. Alopecia UK describes the inheritance as polygenic and says having a close relative with pattern hair loss raises the risk without guaranteeing it.

The British Association of Dermatologists says there are usually no symptoms on the scalp, though some men describe itch, and hairs in the affected areas are first smaller in diameter and shorter before they become absent. The usual pattern is a receding frontal hairline and loss from the top, with the sides and back spared.

Diagnosis is usually based on the history, the pattern and a family history of similar hair loss, with a normal-looking scalp on examination. Alopecia UK adds that a GP or dermatologist may recommend tests of hormone levels, iron stores and thyroid function to rule out other causes. The NHS suggests seeing a GP to find out what is causing your hair loss before going to a commercial hair clinic.

Hair loss can affect self-esteem and body image, and the British Association of Dermatologists encourages people to raise this with their healthcare professional. The NHS says a GP may be able to help with counselling.

Minoxidil (5% liquid or foam) is applied to the scalp. The British Association of Dermatologists says it may slow progression and acts as a hair growth stimulant, needs at least 6 months and possibly up to 12 months before any benefit may be noted, and gives benefit only while it is used. Skin reactions such as dryness, redness, scaling or itching can occur, and it should not be applied to cuts or open wounds. Some people notice extra hair fall in the first 4 to 6 weeks, which the leaflet explains is shedding of hairs that were already at the end of their life cycle.

Finasteride tablets reduce levels of DHT and may slow hair loss and possibly help regrowth. The same leaflet says continuous use for up to 14 months can be needed before a benefit is usually seen, that decreased libido and erectile problems are recognised side effects in approximately 2% of people taking it, and that hair loss restarts after stopping. Alopecia UK says oral finasteride is available via private prescription only, and the NHS says women should not use finasteride. Finasteride is a prescription-only medicine, so whether it suits you is a matter for a prescriber who knows your history.

The NHS is plain that these treatments do not work for everyone, only work for as long as they are used, and may be costly if you have to pay.

The British Association of Dermatologists describes several other approaches. Low-dose oral minoxidil may be at least as effective as topical treatment in certain situations, according to recent research it cites. Dutasteride also reduces DHT, but the leaflet says it has not been convincingly shown to improve on finasteride while side effects were reported more often and for longer.

Platelet-rich plasma, microneedling and low-level laser devices are described as having limited research behind them. The leaflet calls the benefit of PRP unpredictable and says very little research shows microneedling to be a safe and effective treatment, while saying laser light may improve growth but needs further research.

For camouflage, wigs and hairpieces can be synthetic or real hair, and the leaflet says generally only synthetic wigs are available under the NHS. The NHS says synthetic wigs last 6 to 9 months and real-hair wigs 3 to 4 years. Spray fibres can disguise thinning but wash away when the hair gets wet.

The British Association of Dermatologists says surgical treatment is not offered under the NHS but can be sought privately. A hair transplant takes follicles from the back and sides of the scalp, where hair is typically more resistant to miniaturisation by DHT, and places them in balding areas.

Alopecia UK notes that hair transplantation can restore hair in thinning or bald areas but that continued treatment is needed to maintain the hair after it has been restored. If you are considering surgery, our hair transplant decision guide covers questions to ask. As with any procedure, check the surgeon's qualifications and registration.

One practical point from the British Association of Dermatologists is sun protection. Hair protects the scalp from sunlight, so bald areas should be covered with sunscreen, a hat or a wig when you are exposed to the sun, to prevent sunburn and long-term sun damage.

Support groups can help. The NHS points to Alopecia UK for finding support near you, and the British Association of Dermatologists lists Alopecia UK as a patient group.