What is androgenetic alopecia?

Androgenetic alopecia is the most common type of progressive hair loss. It is also known as male-pattern baldness, female-pattern baldness, or just common baldness. It affects about 50% of men over the age of 50, and about 50% of women over the age of 65. In women the severity varies, it may present as widespread hair thinning but in some cases it can lead to complete baldness.

What causes androgenetic alopecia?

Androgenetic alopecia is caused by a combination of genetic and hormonal factors. Dihydrotestosterone (DHT) is the main hormone responsible for androgenetic alopecia in genetically susceptible individuals. DHT causes scalp hair loss by inducing a change in the hair follicles on the scalp. The hairs produced by the affected follicles become progressively smaller in diameter, shorter in length and lighter in colour until eventually the follicles shrink completely and stop producing hair. 

Is androgenetic alopecia hereditary?

Yes. It is believed that genetic susceptibility to this condition can be inherited from either or both parents.

What are the symptoms of androgenetic alopecia?

Androgenetic alopecia affects men earlier, and more commonly, than women.

Males typically become aware of scalp hair loss or a receding hairline, beginning at any time after puberty.

In women, the age of onset is later compared to men, usually occurring in the 50s or 60s. Occasionally, androgenetic alopecia in women may start earlier than this, in the 30s or 40s. In some women, this condition can be associated with an excess of male hormones such as in polycystic ovary syndrome (PCOS). Acne, increased facial hair, irregular periods and infertility are all signs of PCOS.

What does androgenetic alopecia look like?

Androgenetic alopecia looks different in males and females. Hairs in the affected areas are initially smaller in diameter, and shorter compared to hairs in unaffected areas, before they become absent.

In men, the usual pattern of hair loss is a receding hairline, and loss of hair from the top and the front of the head.

In women, hair loss or thinning typically occurs at the crown of the scalp, with complete or nearly complete preservation of the frontal hairline.

How is androgenetic alopecia diagnosed?

The diagnosis is usually based on the history, pattern of hair loss and family history of a similar pattern of hair loss. The skin on the scalp looks normal on examination. Occasionally blood tests may be carried out.

Can androgenetic alopecia be cured?

No, there is no cure for androgenetic alopecia. However, the progression of this condition in both men and women tends to be very slow, spanning several years to decades. An earlier age of onset may predict a quicker rate of progression.

How can androgenetic alopecia be treated?

Licensed topical and oral treatments:

  • Applying 2% or 5% minoxidil solution to the scalp may help to slow down the progression and partially restore hair in a small proportion of males and females. However, this product is expensive and seldom produces a worthwhile long-term improvement. In those who respond, the benefit is only maintained for as long as the treatment is used. Minoxidil has been known to cause irritant or allergic reactions at the site of application.
  • For men, finasteride tablets reduce levels of dihydrotestosterone which may slow hair loss and possibly help regrowth of hair. Continuous use for 3 to 6 months is required before a benefit is usually seen. Decreased libido and erectile dysfunction are recognised side-effects of this treatment. Any beneficial effects on hair growth will be lost within 6 to 12 months of discontinuing treatment.

Unlicensed treatments:

  • For women, medications such as spironolactone, ciproterone acetate, flutamide and cimetidine can block the action of dihydrotestosterone on the scalp which may result in some improvement in hair loss. Spironolactone and ciproterone acetate however should be avoided in pregnancy since they can cause feminisation of a male fetus; both should be avoided during breast feeding. Flutamide carries a risk of damaging the liver.

It is important to note that all of the topical and oral treatments only work for as long as the treatment is continued. Furthermore, none of these treatments are particularly effective.

Wigs and hair pieces:

  • Some affected individuals find wigs, toupees and even hair extensions very helpful in disguising androgenetic alopecia. There are two types of postiche (false hairpiece) available to individuals; these can be either synthetic or made from real hair. Synthetic wigs, and hairpieces, such as a toupee, usually last about 6 to 9 months, are easy to wash and maintain but can be susceptible to heat damage and may be hot to wear. Real hair wigs or hairpieces can look more natural and can be styled with low heat.

Cosmetic camouflage:

  • Spray preparations containing small pigmented fibres are available from the internet and may help to disguise the condition in some individuals. These preparations however may wash away if the hair gets wet (.e. rain, swimming, perspiration), and they only tend to last between brushing/shampooing.

Surgical treatments:

Surgical treatment is not offered under the NHS. This can be sought privately and includes (i) hair transplantation, which is a procedure whereby hair follicles are taken from the back and sides of the scalp and transplanted onto the bald areas, and (ii) scalp reduction which involves the removal of an ellipse from the bald area with closure by stretching of the hair baring scalp. Tissue expanders may be used to stretch the skin in some cases, and in addition the scars from a scalp reduction may be too evident.

Self care (What can I do?)

An important function of hair is to protect the scalp from sunlight; it is therefore important to protect any bald areas of your scalp from the sun to prevent sunburn and to reduce the chances of developing long-term sun damage.

You should cover any bald patches with sun block, your wig or a hat if you are going to be exposed to sunlight.

Telogen effluvium (a type of hair loss)

What are the aims of this leaflet?

This leaflet has been written to help you understand telogen effluvium. It tells you what telogen effluvium is, what causes it, what can be done about it, and where you can get more information about it.

What is telogen effluvium?

It is normal to shed approximately 30-150 hairs from our scalp daily as part of our hair cycle, but this can vary depending on washing and brushing routines. Hair regrows automatically so that the total number of hairs on our head remains constant. Telogen effluvium occurs when there is a marked increase in hairs shed each day. An increased proportion of hairs shift from the growing phase (anagen) to the shedding phase (telogen). Normally only 10% of the scalp hair is in the telogen phase, but in telogen effluvium this increases to 30% or more. This usually happens suddenly and can occur approximately 3 months after a trigger.

What causes telogen effluvium?

Increased hair shedding in telogen effluvium occurs due to a disturbance of the normal hair cycle.

Common triggers of telogen effluvium include childbirth, severe trauma or illness, a stressful or major life event (such as losing a loved one), marked weight loss and extreme dieting, a severe skin problem affecting the scalp, a new medication or withdrawal of a hormone treatment. No cause is found in around a third of people.  

Is telogen effluvium hereditary?

Telogen effluvium is not inherited, and it can affect all age groups and both genders equally.

What are the symptoms of telogen effluvium?

Most people become aware of hair coming out in increased amounts. This is most noticeable after washing or brushing the hair with more hair found in the plug hole, or on the hair brush or comb. Some people will notice increased hair on the pillow in the morning or around the house. Usually there are no symptoms, but occasionally telogen effluvium can be accompanied by tenderness and altered sensations in the scalp known as trichodynia.

What does telogen effluvium look like?

Hair shedding in telogen effluvium is usually from all over the scalp. Hair density decreases in the early stages resulting in reduced volume of hair.

How is telogen effluvium diagnosed?

The diagnosis is usually based on appearance and the history of the hair shedding. The hair may be gently pulled to assess if an increased quantity of hair is shed (although this test may be falsely negative if the hair has been washed within 48 hours beforehand) and occasionally hairs are plucked from the scalp so that they can be examined under the microscope. Very rarely a skin biopsy may be required. 

Can telogen effluvium be cured?

Telogen effluvium usually resolves completely without any intervention as the normal length of telogen is approximately 100 days (3 to 6 months) after which period the hair starts growing again (anagen phase). However depending on the length of the hair, it may take many months for the overall hair volume to gradually return to normal. Telogen effluvium can also return, especially if the underlying cause is not treated or recurs.

How can telogen effluvium be treated?

There is normally no treatment required for telogen effluvium as the hair will start growing by itself once the trigger is removed. Medication does not speed up this process.

A blood test may be suggested to rule out other causes of hair loss, e.g. over- or underactive thyroid.

What if the scalp starts to become visible because of thinning of the hair?

This can happen in severe cases of telogen effluvium in which case various options for helping disguise the hair loss can be discussed with your doctor. It is very unusual that hair thinning in patients with telogen effluvium will be severe enough to require the use of a wig.

Other types of hair loss

There are many other causes of hair thinning including female pattern hair loss (androgenetic alopecia) which may also present in a similar fashion to telogen effluvium and sometimes there is an overlap of these two conditions. Wigs are available with a consultant prescription on the NHS although a financial contribution may be required.

Self care (What can I do?)

  • You may find that joining a patient support group (see below) and meeting other people with telogen effluvium may be helpful for you to adjust to your condition.

Seek unbiased medical help.


Source: British Association of Dermatologists PILs