Anagen Effluvium

Anagen effluvium is abrupt, diffuse hair loss caused by interruption of the mitotic activity of rapidly dividing anagen follicles.

• Occurs within days to 4 weeks after exposure: chemotherapy (cyclophosphamide, doxorubicin, docetaxel, paclitaxel, ifosfamide, etoposide), radiotherapy (scalp doses over 3 Gy cause temporary loss; over 40 Gy permanent), thallium, mercury, boric acid, colchicine overdose, and severe protein malnutrition.
• Up to 65% of patients on chemotherapy develop alopecia. Taxane and busulfan regimens can cause permanent chemotherapy induced alopecia in about 10 to 15%.
• Hair loss is reversible after the stimulus ceases, but regrowth may differ in texture and colour.

• Loss of 80 to 90% of scalp hair within 1 to 2 weeks of exposure, eyebrows, lashes, and body hair also affected.
• Dystrophic anagen hairs (tapered fractures), Pohl-Pinkus constrictions.
• Scalp tenderness and psychological distress; no scarring in most cases.
• Regrowth begins 1 to 3 months after therapy ends and completes in 3 to 6 months.

• Clinical, based on timing with drug exposure.
• Pull test shows dystrophic anagen hairs; trichogram shows over 90% anagen with broken hairs.
• Review drug exposure and occupational or environmental toxins (heavy metals) where cause is unknown.
• Biopsy usually unnecessary; exclude alopecia areata, telogen effluvium, and syphilis.
• Urine or hair thallium and arsenic if toxin suspected.

• Scalp cooling (hypothermia caps) during infusions reduces alopecia in 50 to 65% for anthracycline and taxane regimens (best with docetaxel; less effective with high dose anthracyclines or in haematological cancers).
• Topical minoxidil 2 to 5% twice daily during regrowth may shorten duration of alopecia.
• Gentle hair care: soft brushes, avoid heat and chemical treatments, scalp sun protection.
• Psychosocial: counselling, wigs or scalp prosthetics, head coverings, eyebrow tattooing or microblading.
• Persistent chemotherapy induced alopecia: minoxidil (topical or oral low dose 0.25 to 2.5 mg), spironolactone 50 to 100 mg, bimatoprost for eyelashes, or PRP.
• Remove toxin source in poisoning, with chelation if indicated (thallium: Prussian blue 3 g three times daily).