ABSTRACT
The term telogen effluvium (TE), coined by Kligman in 1961, defines a diffuse and profuse loss of hair in telogen phase. It is the most common cause of diffuse hair loss in young females. TE may affect both sexes, but it occurs more frequently in adult females. TE is defined as a non-scarring, diffuse, hair loss that occurs around 3 months after a triggering event and lasting for about 6 months. The diagnosis of TE indicates an increased loss of hair, acute or chronic, which can be the consequence of five different pathogenetic mechanisms, according to Headington's classification. The diagnosis of TE includes two separate entities, distinguished in acute and chronic, with different causes, onset, symptoms, and outcome. Chronic TE is characterized by increased hair shedding lasting for more than six months. This condition mostly affects middle aged women and frequently remains unexplained since the patient does not remember the causative factor.
