This test produces a trichogram to assess the telogen: anagen ratio but is rarely needed for clinical diagnosis of hair loss.
In people who have telogen effluvium, a larger than normal number of hair follicles become inactive.
It is likely that they involve stem-cell failure at the base of the follicles, which inhibits follicular recovery from the telogen phase.
A 0.1% melatonin or a placebo solution was applied on the scalp once daily for 6 months and trichograms were performed to assess anagen and telogen hair rate.
Hair grows in cycles: anagen is the growth phase; catagen is the transition phase; and telogen is the resting phase.