1)      Male pattern baldness – receding hairline, thining in the crown and later disappearance of hair, finally horseshoe ring of hair in the head, onset by 30 yrs and fully developed pattern by 60 yrs,

2)      Female pattern baldness – thining of hair all over the scalp, intact hairline, onset premenopausal and fully developed postmenopausally,

3)      Excessive shampooing or blow-drying, wearing pigtails, cornrows, tight hair rollers, traction alopecia,

4)      Emotional and physical stress,

5)      Any severe illness, childbirth – usually 3-4 months after the event,

6)      Telogen Effluvium – (N) metabolic (SLE, lymphoproliferative diseases, chronic liver/renal diseases, hypothyroidism, heavy metal poisoning, drugs like beta blockers, anticoagulants, retinoids, carbamazepine, propylthiouracil, immunizations, IDA) or physiologic stress (febrile illness, major injury, dieting, pregnancy, delivery), 1-6 months later symptoms develop, increase hair fall, decreased hair density, thin and lusterless hair, new short hairs more than the usual number, gentle hair pull give about 4/pull, forced hair pull 10-20/pull (more than 20% of hairs are telogen hairs – those hairs with a white bulb and lack of gelatinous hair sheath), hair loss confined to the scalp, no scarring, no other scalp pathology, no scalp inflammation, Mx – If there is a clear history of precipitating stress then no lab works, but if not then do tests to exclude those diseases shown in ht e metabolic stress group, usually spontaneous remission,

7)      Alopecia areata

8)      Anagen arrest -  (N ) – radiation exposure, chemotherapeutic agents,

9)      Tinea capitis

10)    Drug-induced – anticoagulants, gout medications, cancer chemo, vitamin A, antidepressants