Telogen effluvium

What is telogen effluvium?

Telogen effluvium is a type of non-scarring alopecia that occurs when the hair follicle prematurely exits the growth (anagen) phase and enters the resting (telogen) phase, resulting in increased hair shedding. 

It is one of the most common reasons for consultation, particularly in women, and can occur at any stage of life, as numerous triggers can disrupt the normal balance of the hair cycle. 

Signs and symptoms of telogen effluvium

Diffuse, sudden and noticeable hair shedding is seen, typically 2-4 months after a triggering factor, resulting in a perceived overall reduction in hair volume without leading to completely bald areas. 

Causes of telogen effluvium

Common triggers include infections, fever, surgery, periods of intense physical or emotional stress, hormonal changes—such as those occurring postpartum—restrictive diets, rapid weight loss, and nutritional deficiencies, particularly iron and vitamin D deficiency. 

Diagnosis of telogen effluvium

Telogen effluvium is diagnosed through clinical examination by a specialist, based on observation of the scalp. Trichoscopy is used to confirm the diagnosis. This test allows assessment of variability in hair shaft thickness, an increased number of miniaturised follicles, reduced hair density and the presence of follicular units containing fewer hairs. 

Treatment of telogen effluvium

Telogen effluvium is reversible and so has a good prognosis. Treatment focuses on identifying and addressing the underlying cause, as well as patient education, correction of associated deficiencies, and, in some cases, the use of medications to accelerate recovery and improve the regrowth phase.