When hair loss is a sign of something else

Both underactive and overactive thyroid can cause diffuse thinning. Hair usually recovers once levels are treated.

Ask about: TSH and thyroid hormone tests

Higher androgen levels can thin hair at the crown and parting, often with acne or irregular periods.

Ask about: Hormone tests, and options like spironolactone

Low ferritin is common, especially with heavy periods or a vegetarian diet, and is linked to shedding.

Ask about: Ferritin and a full blood count

A major stressor pushes many hairs into the resting phase. Heavy shedding follows 2–3 months later and usually settles within 6 months.

Ask about: What happened 3 months before the shedding

Typhoid, dengue, COVID-19, surgery and other illnesses often trigger temporary shedding.

Ask about: Timeline of illness and recovery

Ongoing stress can keep shedding going and worsen other kinds of hair loss.

Ask about: Sleep, workload, and whether shedding started after a stressful period

Hair thickens in pregnancy, then sheds heavily 2–4 months after birth. It normally returns within a year.

Ask about: Iron and thyroid checks if it lasts longer

Low vitamin D, B12 or zinc are linked to shedding, particularly in vegetarians.

Ask about: Vitamin D, B12 and, if suspected, zinc

An autoimmune condition causing round bald patches, sometimes more. Newer medicines can help severe cases.

Ask about: Steroid injections, and JAK inhibitors for severe cases

Seborrhoeic dermatitis, psoriasis and fungal infections can inflame the scalp and add to hair fall.

Ask about: Whether the scalp is scaly, red or itchy