Androgenetic alopecia: pattern hair loss in men and women, causes and treatment

Androgenetic alopecia is the medical name for male and female pattern hair loss. BAD explains that in a process called miniaturisation, hairs produced by the affected follicles become gradually thinner and lighter in colour until eventually the follicles shrink completely and stop producing hair. A hormone called dihydrotestosterone (DHT) causes this change, and the NHS says finasteride works by stopping testosterone turning into DHT.

It is different from temporary hair loss. The NHS says other types of hair loss may be temporary and can be caused by an illness, stress, cancer treatment, weight loss or iron deficiency. Hair loss caused by a medical condition usually stops or grows back once you have recovered, while male and female pattern baldness is permanent.

BAD says over 190 genes have been identified as contributing to male pattern hair loss, which helps to explain why it affects family members to different degrees and at different ages.

BAD says men can become aware of scalp hair loss or a receding hairline at any time after puberty. The usual pattern is a receding frontal hairline and loss of hair from the top of the head, with the hair at the sides and back spared. There are usually no symptoms on the scalp, though some men describe itch.

In women, BAD says the age of onset is later, usually in the 50s or 60s, although it may start in the 30s or 40s. There is diffuse thinning of the hair, mainly over the top of the scalp, and the mid-parting becomes more visible and widened. The hairline at the front often remains normal.

The NHS says most hair loss does not need treatment, that no treatment is 100% effective, and that not all treatments are available on the NHS, so you may have to pay. Finasteride and minoxidil are the main treatments for male pattern baldness, and minoxidil can also be used for female pattern baldness. They do not work for everyone and only work for as long as they are used.

BAD says male pattern hair loss tends to progress very slowly, from several years to decades, and that an earlier age of onset may lead to quicker progression. It says the same about female pattern hair loss.

For treatment, the NHS says you can expect to see some improvement after 3 to 6 months of finasteride, while BAD says continuous use for up to 14 months can be required before a benefit is usually seen. For minoxidil, BAD says at least 6 months and possibly up to 12 months are needed.

The NHS says you will usually take finasteride for a long time, perhaps several months or years, and should not stop without talking to your doctor, because hair loss will usually come back.

The NHS says finasteride is generally safe to take for a long time. The common side effects, in more than 1 in 100 people, are problems getting an erection, less interest in sex, and problems with ejaculating, which can sometimes carry on even after stopping. BAD quotes decreased libido and erectile problems in approximately 2% of patients.

Serious side effects are rare. The NHS says to call your doctor or 111 now if you get any lumps, pain or swelling in your chest area or discharge from your nipples, and that if you are taking it for hair loss and get low mood (depression), you should stop taking the medicine straight away. If you have thoughts of harming yourself, call 999 or go to A&E.

The NHS says finasteride will not affect your ability to drive, and you can drink alcohol with it. If you miss a dose by less than 6 hours, take it when you remember; if it is more than 6 hours, skip it and do not double up.

There is no home remedy that reverses pattern hair loss. BAD says self-care is mostly about protecting bald areas of the scalp from the sun, because hair normally protects the scalp: cover any bald patches with sun block, a wig or a hat when exposed to sunlight.

BAD says spray preparations containing small pigmented fibres can help disguise hair loss, but may wash away if the hair gets wet. Wigs, toupees and hair extensions can also be helpful. The NHS says synthetic wigs last 6 to 9 months, are easier to look after, can be itchy and hot, and cost less, while real-hair wigs last 3 to 4 years, look more natural and cost more.

BAD says hair loss can have a significant psychological impact, and that it is important to address your emotional wellbeing with your healthcare professional. The NHS says a GP may be able to help arrange counselling, and a support group, such as those listed by Alopecia UK, may help.

The NHS says hair loss is not usually anything to worry about, but occasionally it can be a sign of a medical condition. See a GP if you are worried about your hair loss. The GP may be able to tell what is causing it by looking at your hair, and you can mention if it is affecting your wellbeing and ask what treatments are available.

The NHS also advises seeing a GP to get an idea of what is causing your hair loss before thinking about going to a commercial hair clinic.

NHS care for pattern hair loss is limited to assessment, advice, support and some wigs. The NHS says finasteride for hair loss is available only on a private prescription, and BAD says minoxidil, surgery and PRP are not offered on the NHS. Private clinics and dermatologists provide these.

Be sceptical of treatments marketed with guaranteed results, and ask what happens to your hair if you stop treatment. Ask any private provider to share their findings with your GP.