 As a result, it may displace endogenous testosterone from SHBG and thereby increase free testosterone concentrations, which may in part be involved in its effects.Mesterolone, also known as 1α-methyl-4,5α-dihydrotestosterone (1α-methyl-DHT) or as 1α-methyl-5α-androstan-17β-ol-3-one, is a synthetic androstane steroid and derivative of DHT.It is specifically DHT with a methyl group at the C1α position.