"Fitzpatrick's Color Atlas & Synopsis of Clinical Dermatology"; Klaus Wolff, Richard Allen Johnson, Dick Suurmond; Copyright 2005, 2001, 1997, 1993 by The McGraw-Hill Companies. All Rights reserved.
Telogen effluvium (TE) is probably the second most common form of hair loss dermatologists see. It is a poorly defined condition; very little research has been done to understand TE. In essence though, TE happens when there is a change in the number of hair follicles growing hair. If the number of hair follicles producing hair drops significantly for any reason during the resting, or telogen phase, there will be a significant increase in dormant, telogen stage hair follicles. The result is shedding, or TE hair loss. Read more about hair loss basics.