Hair Growth Cycle

Hairs follow a cyclic pattern as far as hair growth and fall is concerned. It is important to know the normal hair loss pattern, before we diagnose something as abnormal. Approximately 100 hair fall per day. If they keep on falling at the same rate and don’t regrow, the entire scalp would be empty in 3 years. So there is a hair cycle where hair fall and get replaced by the new hair.

Hair GrowthIt can be divided in 3 phases:

  1. ANAGEN PHASE: This is the first and the longest phase approx. 3 years in duration. This is the active phase so the length of the hair follicle increases in this phase only.
  2. CATAGEN PHASE: This is a transition phase of around 1 to 2 weeks duration.
  3. TELOGEN PHASE: This is the terminal phase of approx. 3 months duration. Once a hair enters into telogen phase it falls in 3 months.

According to the pathology of the disease, one or more phases of the hair cycle can be affected, which in turn determines the pattern of hairless and treatment.