Pregnenolone absorption came in to question this week as oral steroids seldom reach increased levels in circulation due to the first pass through the liver. Unfortunately most of the research on Pregnenolone was performed in the 40s and there is limited access to this literature. Fortunately as it is used in athletics there is some research on doping markers. Also a recent study showed “Pregnenolone-pretreated subjects showed significantly less sedation following diazepam (p<0.03)”. So although it may not be getting into the blood as pregnenolone, it is absorbed and has a clinically significant affect on the body.
Saudan C, Desmarchelier A, Sottas PE, et al. Urinary marker of oral pregnenolone administration. Steroids. 2005;70(3):179-83.
Saudan C, Baume N, Mangin P, et al. Urinary analysis of 16(5alpha)-androsten-3alpha-ol by gas chromatography/combustion/isotope ratio mass spectrometry: implications in anti-doping analysis. J Chromatogr B Analyt Technol Biomed Life Sci. 2004;810(1):157-64.
Meieran SE, Reus VI, Webster R, et al. Chronic pregnenolone effects in normal humans: attenuation of benzodiazepine-induced sedation. Psychoneuroendocrinology. 2004;29(4):486-500.