Alloepipregnanolone, a pregnane with anesthetic, hypnotic, and sedative properties, interferes with the development of rapid tolerance to the anxiolytic effect of ethanol.
On day 2, pretreatment with a 0.20 mg/kg dose of Alloepipregnanolone blocks the development of rapid tolerance to the anxiolytic effect of ethanol. However, there is a significant decrease in the anxiolytic effect in the control groups that received ethanol on both days (EE), suggesting that the 1.5 g/kg dose of ethanol results in rapid tolerance. The post hoc analysis confirms that the 0.20 mg/kg pretreatment with Alloepipregnanolone blocks the rapid tolerance compared to the control groups, although the 0.10 mg/kg dose only partially blocks the development of such tolerance. However, the 0.05 mg/kg dose has no effect on the development of rapid tolerance to ethanol[1].
[1]. Debatin T, et al. Effect of isopregnanolone on rapid tolerance to the anxiolytic effect of ethanol. Rev Bras Psiquiatr. 2006 Mar;28(1):18-23.