What is telogen effluvium?
Telogen effluvium happens when a larger-than-usual number of hairs are pushed prematurely into the resting/shedding phase of the hair cycle, all at once. The result is noticeable, diffuse shedding across the whole scalp — rather than the patchy or patterned loss of other conditions. Crucially, it's a temporary disruption of the cycle, not destruction of the follicles, which is why it typically recovers.
Why is the shedding delayed after the trigger?
This is the part that confuses people: the shedding usually appears a couple of months after the triggering event, because of how the hair cycle works. So you might feel fine now and suddenly shed hair from a stressor, illness or event that happened weeks earlier. This delay is why people often can't immediately pin down the cause — but a doctor can usually connect the timeline.
Common triggers
Childbirth (postpartum shedding is a classic example) Illness, high fever or surgery Significant physical or emotional stress Crash dieting or rapid weight loss Nutritional deficiencies (e.g. iron) Some medications and certain medical/hormonal changes Identifying the trigger is central, because addressing it is what allows recovery.
Is it permanent?
Will my hair grow back? For most people, this is the reassuring part: telogen effluvium is usually temporary, and hair typically recovers over several months once the trigger has passed or been addressed, as the cycle normalises. It doesn't usually cause permanent loss on its own. That said, if shedding is prolonged or doesn't recover, it's worth checking for an ongoing trigger (like an untreated deficiency) or another underlying cause. Individual recovery varies.
What helps — and when to see a doctor?
The main "treatment" is identifying and addressing the trigger — managing stress, recovering from illness, correcting a deficiency (confirmed by testing), and supporting general health. Gentle hair care helps in the meantime. See a doctor if the shedding is heavy or prolonged, doesn't recover, or you're unsure of the cause — a dermatologist can confirm it's telogen effluvium (rather than another cause) and check for treatable triggers. Individual results vary.