pseudoalopecia

Pseudoalopecia is a descriptive term used in dermatology to refer to patterns of hair shedding or thinning that resemble alopecia but are not due to primary destruction of hair follicles. It is not a single disease but a label applied to non-inflammatory or non-scarring conditions that can mimic true hair loss. The term emphasizes that the follicles themselves are often preserved and that regrowth is possible once the triggering factor is addressed.

Common mechanisms include telogen effluvium, where systemic stressors such as illness, childbirth, surgery, or certain medications induce excessive shedding; traction-related shedding from tight hairstyles; chemical or thermal damage causing breakage of hair shafts above the scalp; and certain hair shaft disorders that render hairs fragile. Psychogenic factors, including trichotillomania, can produce irregular shedding that resembles patchy alopecia but typically lacks inflammatory or scarring features.

Diagnosis relies on clinical history and examination, with dermoscopic or trichoscopic findings helping to distinguish non-scarring patterns from inflammatory or scarring alopecias. Hair pull tests may be positive or negative depending on the underlying cause, and scalp biopsy is reserved for equivocal cases where the diagnosis is unclear.

Management targets the underlying cause and prevention of further damage. This may involve altering hair care practices, treating nutritional deficiencies, addressing systemic illnesses, modifying medications, and providing psychological support when appropriate. In cases of telogen effluvium or mechanical shedding, prognosis is generally favorable with hair regrowth occurring after the precipitating factor is removed.