Alopecia is the medical term for hair loss and is common in both men and women. Alopecia usually, and most noticeably, affects the scalp but can affect any part of the body where hair grows. Alopecia has many different causes and depending on the cause, different treatment will be recommended.
Normally hairs grow out of hair follicles in a cycle – the amount of time the hair stays in the ‘active’ part of the cycle determines the length of hair growth. As part of this cycle, it is normal to lose up to 100 scalp hairs per day as new hairs push the old hairs out of the follicle. If higher numbers of hairs are lost than is replaced, hair thinning or loss is seen.
Types of hair loss include non-scarring alopecia, where the hair follicles are intact with the potential for hair to re-grow and scarring alopecia, where the hair follicles are destroyed so that hairs cannot grow back. Below are the most common causes of alopecia, grouped in to these main types.
Androgenetic alopecia: this depends on genetic factors and is affected by androgen (male hormone) levels. It is very common in men. In men, the frontal hairline recedes and this is followed by a bald patch appearing on the crown of the head. In women, usually the hair loss occurs over the hair parting line.
- This condition is normally treated with gels, foams and lotions (e.g. minoxidil)
- Tablets that reduce the amount of androgen (male sex) hormones in the body (e.g. finasteride, spironolactone).
Alopecia areata (AA): this usually results in round patches of hair loss on the scalp, though can affect the whole scalp and even the whole body including areas such as eyelashes. Sometimes this is related to other ‘autoimmune conditions’ and blood tests may be taken to look for possible associations. AA may resolve spontaneously (this is most likely if the patches are small), but some cases may be progressive.
- Treatment can include injecting steroids in to affected areas, but this may not be practical if large areas are affected.
- A method called contact sensitization with the chemical diphencyprone (DCP) can be used to stimulate the immune system in the area of concern.
Medical conditions & medications: medical conditions such as anaemia and thyroid disease may cause hair loss. Medications used to treat conditions can also lead to alopecia.
Blood tests may be required to look for an underlying cause.
- Treating the underlying cause is the most important focus here.
Telogen effluvium: this may occur after a significant illness, personal stress (e.g. death of family member) or after childbirth. Hair loss usually affects the whole scalp diffusely and is related to an increased shedding of hair. It usually starts within a few months of the event and reverses within months.
Tinea capitis: also known as scalp ringworm, is a fungal infection. The fungus occupies the hair shaft and causes the hair to break off.
- Antifungal shampoos are generally not effective alone so a course of oral antifungal tablets (e.g. terbinafine or azole antifungals) is usually needed. Blood tests may be required for monitoring during treatment. These medicines may interact with other treatments so it’s important to inform the specialist of your regular medications.
Traction alopecia: this can occur if excess traction/load is put on the hair, for example the overuse of straighteners or curlers or having the hair in a tight ponytail or plaits/braids. Avoiding the traction is the most important factor in treatment.
Scarring alopecia: early diagnosis and treatment will help prevent further hair follicle destruction Causes of scarring alopecia are most commonly caused by the following:
Discoid lupus erythematosus (DLE). This is a form of the autoimmune condition lupus, which typically affects the skin alone and rarely affects any other organ. On the skin (often affecting the face and ears), it appears as crusted red plaques but also commonly causes alopecia in hair-bearing areas. Afterwards, the scarred areas may appear discoloured.
- Cessation of smoking and sun protection are of great importance in DLE.
- Courses of potent topical corticosteroids are the mainstay of treatment.
- Oral treatments such as hydroxychloroquine and methotrexate are commonly used. The specialist will discuss the risks and benefits of any tablets used and the need for monitoring blood tests.
Lichen planopilaris (LPP) and its subtype frontal fibrosing alopecia. This is an inflammatory condition which is usually associated with lichen planus of the skin (seen as small itchy purplish lumps or ulcers and white lacy patterns in the mouth). It is usually seen as white scars in the hair, also redness and scale may be seen around the hair follicles.
- Courses of potent topical corticosteroids or steroid sparing agents (e.g. tacrolimus)
- Steroid injections are possible where the areas of hair loss are small.
- Tablets such as hydroxychloroquine, methotrexate, azathioprine and ciclosporin may also be used. These require monitoring blood tests and the risks and benefits need to be weighed up with the specialist.
- Doxycycline (a tablet antibiotic) used for months can be helpful due to its anti-inflammatory properties.
- Isotretinoin (typically a medication used for acne) has been used with success. This tablet is not appropriate in pregnancy or in females wishing to become pregnant.