What is the cause of telogen effluvium?
In a normal healthy person’s scalp about 85% of the hair follicles are actively growing hair (anagen hair) and 15% are resting hair (telogen hair). A hair follicle usually grows anagen hair for 4 years or so, then rests for about 4 months. The resting or telogen hair has a club or bulb at the tip. A new anagen hair begins to grow under the resting telogen hair and pushes it out. Thus, it is normal to lose up to about 100 hairs a day on one’s comb, brush, in the basin or on the pillow, as a result of the normal scalp hair cycle. If there is some shock to the system, as many as 70% of the anagen hairs can be precipitated into telogen, thus reversing the usual ratio. Typical precipitants include: • Illness, especially if there is fever • Surgical operation • Accident • Childbirth • Nervous shock • Weight loss or unusual diet • Certain medications • Discontinuing the contraceptive pill • Overseas travel resulting in jetlag • Excessive sun exposure The resting scalp hairs, now in the form o
