Fleas are blood-feeding insects. Pain and itching results from an allergic reaction to the materials that the fleas inject into the skin at the time of the bite.
Review Date: 11/20/2012 Reviewed By: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.