If propecia has been successful treating my Diffused Patterned Alopecia, should I still have a positive result from the Hair Pull Test (i.e., still find hairs after conducting the Test in the balding areas)?
The hair pull test should be done by the physician, and not by the patient, as it is more complex than the name makes it out to be. Just pulling on some hairs and seeing clumps of hair fall out does not mean you have a positive hair pull test. The hair pull test is performed by taking a few strands of hair between the thumb and forefinger and pulling on them gently. Hairs in anagen (growing) should remain rooted in place while hairs in telogen should come out easily. You then figure out what percent of the hair is in the telogen stage. For more information on the cycles of hair growth, see Hair Follicle Cells Growth Stages.
Shedding of hair can be variable from day to day and is greater in certain seasons (spring and autumn). Washing you hair prior to having a hair pull test can also affect the results. Genetic hair loss does not cause a positive hair pull test. And it should go without saying, but the image to the right is NOT the actual hair pull test, and you shouldn’t have to worry about your doctor doing this to your head when conducting the test.