Excessive shedding of normal club hairs can be brought about by a number of stresses: parturition, febrile illness, psychological stress, crash diets, drugs (Table 4). These factors may cause termination of the growing phase (anagen) of the hair follicles and transformation into the resting phase (telogen), causing a telogen fallout 2 to 4 months later. The normal average scalp has 100,000 hairs. Approximately 90% are in anagen, 10% in telogen. Normal average daily hair fallout is 100 hairs. With telogen effluvium, the anagen/telogen ratio may be shifted to 70% anagen, 30% telogen, with average daily shedding of 300 hairs. Treatment depends on determining the cause and correcting it.

Diffuse thinning over the entire scalp with widening of the part everywhere on the scalp.

A second example.