Hair loss

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Androgenetic alopecia


Androgenetic Alopecia is recommended in the deforestation of the central scalp area.


Alopecia is a normal phenomenon due to androgens and appears to people with a genetic predisposition.

Alopecia is probably polygenically inherited.

Initially, a bipartite retreat of the anterior line of the scalp is observed, which then takes the shape of the letter “M”.

In the next stage hair loss occurs in the area of the shearing, which eventually results in deforestation of the entire central area of the scalp.

Alopecia can first manifest at any time after puberty and the phenomenon is usually completed when the patient is about 40 years old.


Normal hair pockets are transformed into follicles that produce fibrous hairs.

The hairs are replaced by a thin, coarse coat of shorter length and a reduced diameter.

Over time the atrophy of the hair pockets continues and eventually the scalp looks smooth and polished. The hair pockets disappear.

There is an increase of secondary tribal hair on the sternum, armpits, genital organs and the beard.

Androgenetic alopecia in women


Androgenetic alopecia in women is a common, hereditary condition in which there is a diffused thinning of hair in the central area of the head, which begins at a relatively early age. It has nothing to do with hair loss due to advanced age that appears during the 6th to 8th decade of life.


Family history of female type alopecia can be reported either on the father’s side or on the mother’s side.

Female patients rarely arrive in complete deforestation of the scalp, as men do.

The hereditary type thinning of the scalp first manifests during puberty or the 3rd and 4th decade of Life and culminates in the 4th decade of life.

The loss is gradual and not sudden or massive.

Menstruation is normal and occurs at a normal rate. The great loss of blood causes iron deficiency and increase of hair loss. Pregnancy develops naturally and there are no infertility problems or galacorrhea.

Some medications cause thinning of the hair. The hair reappear after discontinuation of the drug.


Most women have gradual hair loss in the central area of the scalp, with no posttemporal regression of the anterior line.

The hair density on the scalp decreases.

In the central area the diameter of the hairs varies. Many microscopic (thin and short hair) are observed. Hair that form the anterior line of the scalp are normal.

The diameter of the hair decreases over the years. This is particularly noticeable in patients who make “plaits”.

Alopecia areata


  • Sudden complete loss of hair of a well-described, usually circular, area of the scalp.


  • It is more common among children and young adults.
  • There is a sudden occurrence of one or more areas of 1-4 cm in size, showing hair loss.
  • The eyelashes, the beard or rarely other areas of the skin may also be affected.
  • In young patients very often there is universal alopecia. Cycles of hair and hair loss appear alternatively.
  • The loss of all body hair is very rare.
  • Patients very often attribute the condition to increased stress, but there is not enough evidence to support this view.
  • Hair growth is restored in 1-3 months but can be combined with loss of hair in other areas of the head.
  • The probability of complete and permanent hair restoration is great in patients with limited disease. On the contrary, prognosis is not good in patients with extensive alopecia.


  • The clinical picture varies
  • The skin can be completely deforested or have short hair.
  • The body of the hair is not well formed resulting in breakage at the point that exits the skin.
  • The new hair that appear usually have the same color and texture as the ones that were lost, although sometimes they are subtle and colorless.


  • It is a self inflicted recurrent eradication of hair, resulting in the loss of a significant amount of it.
  • The eradication of hair is a mental concern of the patient for many hours a day.


  • It is an ugly habit that is usually observed in children.
  • It can also occur in adolescents and adults
  • The female sex is affected 2.5 times more than the male.
  • The patients wrap the hair around their finger and then pull it or rub it up to the point of extraction or breakage.
  • They usually prefer areas of the scalp that reach easily, such as the Metotemporal, the Frits and eyelashes.
  • Initially the patient is occupied with this in a period of inactivity, while watching TV or just before bedtime.
  • Parents don’t usually perceive this child’s habit.
  • This behavior appears in periods of stress and may be an obsessive-compulsive manifestation.
  • This problem can be chronic and often resolves itself.


  • A deforested area with irregular angular boundaries is observed.
  • In this area the hair is sparse.
  • The skin is not completely deforested and smooth as in the alopecia areata.
  • There are short, broken hair of varying length, randomly distributed in the affected area.