Related Experiment Video
Updated: Jun 14, 2026

Establishment of Rat Models Mimicking Gender-affirming Hormone Therapies
Published on: January 10, 2025
Analysis of non-ketoic steroids 17alpha-methylepithiostanol and desoxymethyl- testosterone in dietary supplements
Masato Okano1, Mitsuhiko Sato, Ayako Ikekita
1Anti-Doping Centre, Mitsubishi Chemical Medience Corporation, 3-30-1 Shimura, Itabashi-ku, Tokyo, Japan. Okano.Masato@mk.medience.co.jp
Abstract:
Dietary supplements containing 17alpha-methyl-2,3-epithio-5alpha-androstane-17beta-ol (17alpha-methylepithiostanol), which is a 17-methylated analogue of epithiostanol or a prodrug of desoxymethyltestosterone (17alpha-methyl-5alpha-androst-2-en-17beta-ol), have recently appeared on the Internet. 17alpha-Methylepithiostanol and desoxymethyltestosterone are classified as prohibited substances on the World Anti-Doping Agency (WADA) list. Two preparations, EPISTANE and P-PLEX, were obtained from the Internet so that their contents could be investigated. This study involved gas chromatography/mass spectrometry (GC/MS) analysis after trimethylsilyl (TMS) derivatization, liquid chromatography/mass spectrometry (LC/MS) in atmospheric pressure photoionization (APPI) mode and nuclear magnetic resonance (NMR) spectroscopy. Analysis using LC/MS in APPI mode would be a useful tool for detecting heat-labile and non-polar steroids.Although the labelling of EPISTANE indicates that it contains 17alpha-methyl-2alpha, 3alpha-epithio-5alpha-androstane-17beta-ol only, 17alpha-methyl-2beta,3beta-epithio-5alpha-androstane-17beta-ol and desoxymethyltestosterone were identified in the supplement. The results showed that P-PLEX contained desoxymethyltestosterone and its isomer 17alpha-methyl-5alpha-androst-3-en-17beta-ol. Urine samples can be screened after EPISTANE or P-PLEX administration using the normal screening procedure for anabolic steroids with GC/MS.
Related Concept Videos
Overview of Fatty Acid Metabolism
Fatty acids are catabolized in a process called beta-oxidation, which takes place in the matrix of the mitochondria and converts their fatty acid chains into two-carbon units of acetyl groups. The acetyl...
Pharmaceutical Alternatives: Stability-Related Therapeutic Nonequivalence

