Diagnosis
Pattern hair loss is gradual over years, in specific zones, with progressively thinner shed hairs.
Pattern hair loss is gradual over years, in specific zones, with progressively thinner shed hairs. Telogen effluvium is sudden, diffuse, full-thickness shedding 2–4 months after a trigger.
How to tell pattern hair loss from telogen effluvium. They’re the two most common diffuse hair-loss patterns and they’re very different.
Pattern hair loss (androgenetic alopecia): gradual progression over years, concentrated in specific zones (temples and crown in men, central scalp in women). Shed hairs are progressively thinner over time, a sign of follicle miniaturisation.
Telogen effluvium: sudden onset of diffuse whole-scalp shedding, typically starting 2–4 months after a physiological trigger (illness, childbirth, severe stress, new medication). Shed hairs are full thickness, not miniaturised.
The two can also coexist. TE on top of pre-existing pattern hair loss is a common reason pattern loss seems to suddenly worsen.
Full diagnostic guide: regrowthindex.com/articles/whats-causing-my-hair-loss