The hair shampoo "two in one" formulation has been developed according to the most recent scientific researches based on the synthetic thymus extract, substance for its features identycal to the natural one, protected by international patent. (Nr. European Patent: 97 933 617.9 - Nr. International Patent: PCT/DE 97/0161). The effectiveness in case of androgenetic alopecia is documented. The true innovation consists in the hair treatment "two in one" that, provided with a fixing lotion at the same time, carries out two functions in one product.