Tags: Drug.
4-Androstene-3617-trione (4-AT; also marketed as 6-OXO or 4-etioallocholen-3617-trione) is a drug or nutritional supplement that may increase the testosterone-estrogen ratio but has no proven effect on body composition. Its use can be detected in urine.4-AT is a potent irreversible aromatase inhibitor that inhibits estrogen biosynthesis by permanently binding and inactivating aromatase in adipose and peripheral tissue.
