Types of Hair Loss
| Type | Pattern | Key Cause | Treatment |
|---|---|---|---|
| Androgenetic alopecia (AGA) | Temple recession + vertex thinning (men); crown thinning (women) | Genetics + DHT sensitivity | Minoxidil; finasteride (men); dutasteride |
| Telogen effluvium | Diffuse shedding across whole scalp | Stress, illness, post-partum, crash diet (3 months delay) | Treat cause; usually self-limiting |
| Alopecia areata | Patchy circular bald areas | Autoimmune T-cell attack on follicles | Steroid injections; JAK inhibitors; DPCP |
| Traction alopecia | Hairline recession where hair is pulled | Tight hairstyles, extensions, braids | Remove traction; follicle preservation |
| Scarring alopecia (lichen planopilaris) | Permanent loss at centre of scalp; follicle destruction | Autoimmune; often irreversible | Specialist dermatology; early anti-inflammatory |
| Hypothyroid hair loss | Diffuse; outer third of eyebrows often lost | Underactive thyroid | Levothyroxine restores hair |
Blood Tests for Hair Loss
- TSH + Free T4 — hypothyroidism causes diffuse hair loss
- Ferritin — iron deficiency depletes hair follicles (target >70 μg/L for hair growth)
- FBC — anaemia, inflammatory markers
- Testosterone + DHEAS + SHBG — elevated androgens in women (PCOS, CAH)
- ANA, anti-dsDNA — autoimmune workup if alopecia areata or scarring alopecia
- Zinc, vitamin D — deficiencies associated with diffuse hair loss
Ferritin Target for HairStandard 'normal' ferritin (>15 μg/L) is insufficient to support hair growth. Most dermatologists recommend targeting ferritin >70 μg/L for optimal hair follicle support — supplementation may be needed.
Does stress cause hair loss?
Yes — telogen effluvium. Physical or emotional stress (illness, surgery, bereavement, crash diet) pushes follicles into the resting phase. Hair falls out 2–4 months after the trigger. It's self-limiting once the stress resolves.
Does minoxidil work?
Yes — topical minoxidil (2% women; 5% men; or 2% oral) prolongs the anagen (growth) phase and increases follicle size. It takes 4–6 months to see results and must be continued — hair loss returns if stopped.
What are JAK inhibitors for alopecia areata?
Baricitinib (Olumiant) and ritlecitinib (Litfulo) are JAK inhibitors now NICE-approved for severe alopecia areata. They restore hair growth in ~40–50% of patients — the most significant advance in AA treatment in decades.
Is hair loss from chemotherapy permanent?
Usually not. Anagen effluvium from chemotherapy is temporary — hair typically regrows within 3–6 months after treatment ends. Scalp cooling during chemotherapy can reduce severity.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.