Dictionary > Telogen

Telogen

Definition
noun
The quiescence phase of the hair cycle
Supplement
The hair cycle is the cyclical phases of growth of hair. It is comprised of the following stages: anagen, catagen, telogen, and exogen. Each hair fiber goes through these stages. However, the hair fibers are at different stages of the hair cycle that occur simultaneously.
Telogen is the third phase of the hair cycle, following the transitional phase catagen. Telogen is the phase when the hair is resting, thus, it is also called the quiescence phase. During this stage, the hair follicle enters a dormant stage for several months, depending on its location in the body. For scalp hair, the telogen lasts for about 100 days. The phase is longer for hairs on the eyebrow, eyelash, arm, and leg.1
In telogen, the hair follicle regresses to half of its size and consequently lies closer to the upper epidermis. The hair follicle is now completely at rest whereas the club hair (i.e. hair with a club-shaped bulb in a resting state prior to shedding) is completely formed. 1 After telogen, the hair is shed (exogen) as the base breaks free from the root. The cycle repeats when a new hair shaft grows, which marks the next anagen phase.
See also:

Reference(s):

1 Peytavi, U. (2008). Hair growth and disorders. Berlin: Springer. p.10


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