Telogen effluvium
Diffuse temporary shedding triggered when stress, illness, surgery or medication pushes many follicles into telogen simultaneously. It is self-limiting and must be distinguished from pattern loss before any transplant decision.
Telogen effluvium is diffuse, temporary shedding caused by timing rather than follicle death: a physiological stressor pushes an abnormally large cohort of follicles out of growth and into the telogen resting phase together, and two to three months later — the length of telogen — the shed arrives all at once. The delay is the diagnostic signature, and the reason patients rarely connect the shedding to its cause.
Triggers are the standard list of systemic events: significant illness and high fever, surgery, childbirth, rapid weight loss and crash dieting, iron deficiency, thyroid dysfunction, some medication starts and stops, and severe psychological stress. The acute form resolves as follicles cycle back over months once the trigger has passed; a chronic form exists in which shedding fluctuates for longer, more often in women, and demands a more patient workup. Reviewing the three months before onset, rather than the week of it, is the history-taking habit that finds triggers.
The clinical job is separation from pattern loss. Effluvium sheds diffusely — including the sides and back that androgenetic loss spares — shows increased shedding on a gentle pull test, and on trichoscopy lacks the calibre diversity of miniaturisation. The two coexist constantly: an effluvium often unmasks early pattern loss by thinning what was already borderline, and the patient arrives blaming the trigger for the whole picture. History, examination and basic laboratory screening sort cause from background; shed hairs carry the club-shaped telogen root, visible under magnification — another quick separator.
For a surgical clinic the term is mostly a brake. Shedding that has not been diagnosed is not a transplant indication; operating into an unrecognised effluvium wastes grafts on a scalp that would have recovered, and surgery is itself a trigger — post-operative shock loss is effluvium by another name. The honest sequence has not changed in decades: diagnose, correct what is correctable, wait out the cycle, and reassess before anyone draws a hairline.