Alopecia is a group of diseases characterized by hair loss. There are different types of alopecia: androgenetic (hereditary), circular, cicatricial, those caused by medication or systemic diseases, traumatic and others.

Androgenetic alopecia occurs most often. It is characterized by gradual thinning and hair fall in symmetrical areas of the head under the influence of androgen hormones. These processes occur in genetically predisposed people. Men are more likely to become bald, with a displacement of the front hairline backwards and thinning of the hair on the forehead. In the beginning, the hairs are replaced by thinning, fine, almost colourless hairs (velus hairs), which eventually also fall off. The scalp becomes smooth, shiny and slightly atrophies with age. Usually the hairs located in the occipital area are not affected.

In women, baldness develops more slowly and is expressed by thinning of the hair on the crown of the scalp ( its uppermost part ) and less frequently in the frontal-orbital region. In these areas the hair is thinned without the baldness characteristic of men. Sometimes it is combined with the appearance of dandruff, hirsutism (increased hair in the chin, upper lip, chest, inner thighs) and itching.

Alopecia areata (Circular alopecia) is characterized by circular hair loss, which may recur. The cause of its occurrence is still unclear, but autoimmune processes and its association with some autoimmune diseases (thyroiditis, vitiligo, etc.)

It presents with circular hairless patches that can grow, merge or lead to complete balding. It begins with the appearance of one, two or several circular bald spots. It is characterized by smooth, soft and shiny skin, which may sometimes be slightly red. The shaved area may expand within a few weeks or become covered with hair again. The disease is chronic and recurrent.

Cicatricial alopecia can be caused by a diverse group of diseases that destroy the hair follicle, replacing it with connective tissue, resulting in permanent hair loss. The group of diseases causing this type of alopecia includes lupus erythematosus, lichen planus, hair inflammations, etc.