Since alopecia areata might be due to an aberrant T-cell-mediated immunity, the purpose of our study was to compare the results obtained with Thymopentin to those of topical sensitizing therapies, such as squaric acid dibutylester or diphencyprone. Statistical analysis showed no differences between the results obtained with these two therapies. Therefore, Thymopentin can be considered to be a new therapeutic agent which, like the classic topical drugs squaric acid dibutylester or diphencyprone, has immunoreactive properties and might provide some hope to patients with severe alopecia areata.