Results of new hair weight studies on Propecia were announced at the recent International Society of Hair Restoration Surgery (ISHRS) annual meeting. According to the presenter, Dr. Janet L. Roberts, the results show that not only does Propecia increase the number of hairs growing but the thickness and volume of hairs.
The study was a randomized, placebo-controlled, double-blind study conducted over 96 weeks in men aged 18-40 with mild to moderate hairloss. Sixty-six men participated in the study, half on placebo and half on Propecia. Hair was clipped from a 1cm area and was both degreased and dehydrated.
Hair weight increased by around 20% in the Propecia group and decreased by 15% in the placebo group. The hair weight increase was greater than could be accounted for in just the regrown hairs, indicated that overall hair thickness in the existing hairs also increased.
Hair counts were found to be similar to the vertex studies. The count of hairs in the anagen (growth) phase increased 26.4% which also indicates that the growth phase of existing hairs is also being prolonged.
The combination of a longer growth phase in hair as well as the increase in thickness of existing hair may account for the fact that many study participants in the large scale studies showed better improvements in the appearance of their hair than might be expected by just looking at how many hairs were regrown.
Dr. Roberts also mentioned that she is conducting followups with patients in the original FDA studies who are now in their 5th to 6th year of treatment and said that many are showing continued improvement and even new growth in the temple areas of their scalp. No specific results for these individuals were announced, however.