Alopecia areata is characterized by patchy scalp hair loss which occasionally affects every hair follicle on the scalp (alopecia totalis), or body (alopecia universalis).

The disease usually occurs between the the ages of adolescence and 30 years, but can appear at any age, affecting both sexes equally. Alopecia Areata has a rapid onset but tends to spontaneously reverse.

The cause of Alopecia Areata is unclear, however, genetic factors, auto-immune mechanisms, and the occurrence of stressful and/or emotional problems shortly before the hair loss are all thought to influence the condition.

Treatments for the disease include topical sensitizers, steroid shots, squaric acid dibutyl ester, diphencyprone, and hypnotherapy.

Cicatricial alopecia is hair loss which occurs with the destruction of the hair follicles.

It can be caused by a disease affecting the follicles themselves, or by some process external to them. The follicles may be absent as a result of trauma such a burn or a blow or cut to the head or they may have been destroyed by a specific infection.

The hair loss can be patchy or diffuse (evenly spaced). A biopsy is usually performed to identify the exact cause of this type of alopecia.

Treatment for cicatricial alopecias are limited as they are usually permanent, however, anti-inflammatory applications and systemic or topical corticosteroids are often used to reduce the inflammation and slow the progress of the disease.

Trichotillomania is the loss or damage of scalp hair through repeated pulling or twisting due to irresistible compulsive impulses.

Trichotillomania is more common among children than adults and occurs more than twice as frequently in women than in men. It often occurs with bulimia nervosa in teenage girls.

The clinical feature of Trichotillomania is plucked hair from the side of the scalp favouring the “dominant” hand. Occasionally, the whole scalp is affected and, in rare cases, other body sites are involved. In some cases the hair can be chewed, eaten and/or swallowed; this is called Trichophagy.

The condition is often compared to other “comforting” habits, such as thumb sucking and nail biting. Behavioral modification through hypnotherapy and aversion therapy, psychotherapy, and medication with imipramine or clomipramine are treatments used with varying degrees of success.

This is the most common cause of hair loss.  The development of genetic hair loss is associated with the shortening of the anagen (growing) phase of the hair cycle and consequently with an increase in the proportion of telogen (resting) hairs. There is a reduction in the size of the affected follicles, which results in a reduction in the diameter of the hairs that they produce. This is an essential feature of this type of hair loss, which accounts for the thinning of the hair and the widening of the partings.

Female genetic hair loss affects over 30% of women.  The hair loss is typically diffuse (evenly spread over the scalp) and affects the frontal and vertex (crown) areas with similar severity. Often a band of slightly denser hair is retained along the frontal hairline. Also, women can exhibit a normal amount of hair in the front area of their scalp, which gradually thins out as you look farther back near their crown. Called a “Christmas-tree” look, this is also indicative of a genetic condition.

E. Ludwig categorized female genetic hair loss into three grades. Although other classifications have been developed, as with the Hamilton-Norwood scale for men, dermatologists, trichologists, and researchers most often use the Ludwig scale to categorize the type and extent of hair loss in women, devise an appropriate treatment and evaluate whether the condition is improving or worsening.

Source: Ludwig E. Classification of the types of androgenetic alopecia (common baldness) occurring in the female sex. British Journal of Dermatology, 1977; 97: 247-254.

This is the most common cause of hair loss.  The development of genetic hair loss is associated with the shortening of the anagen (growing) phase of the hair cycle and consequently with an increase in the proportion of telogen (resting) hairs. There is a reduction in the size of the affected follicles, which results in a reduction in the diameter of the hairs that they produce. This is an essential feature of this type of hair loss, which accounts for the thinning of the hair and the widening of the partings.

The onset of male genetic hair loss is linearly related to age; that is, 20% of men experience some hair loss by age twenty; 30% of men experience some hair loss by age thirty, and so on. The hair begins to recede at the temples and thin in the vertex (crown) area. Eventually, the entire fronto-vertex (between the hairline and crown) area of the scalp can be involved.

In order to assess the extent of genetic hair loss in men, dermatologists and trichologists commonly use the Hamilton-Norwood scale. The Hamilton-Norwood scale helps hair loss experts and patients alike monitor the state of loss, devise an appropriate treatment regimen and evaluate whether the condition is improving or worsening.

Traction alopecia is the breaking of the hair by friction or tension due to vigorous brushing, blow drying, and/or chemical overprocessing.

The area of the scalp most affected tends to be around the hair line. The hair usually regrows fully.

Hair strengthening treatments and hair styling changes are used to help improve the condition.

This hair loss condition, which occurs mainly in women, is usually caused by a temporary disturbance to the hair cycle causing the growing (anagen) hairs to prematurely enter the resting (telogen) phase of the hair cycle.

Stress, illness, medication, anemia, and weight loss are the most common causes, however, many other factors can also influence this condition.

The treatment for telogen effluvium depends on why the individual is losing his/her hair.