Possible Interaction: Ethanol and Ondansetron

“Pretreatment with ondansetron significantly attenuated several of the subjective pleasurable effects of alcohol , and also decreased the subjective desire to drink.”

“In a recent study (Johnson et al. 1993) we found that a single oral dose of the 5-HT3 receptor antagonist ondansetron (4 mg) in healthy male volunteers attenuated some of the pleasurable effects of a tow dose of alcohol (580 ml lager).”

“There is, for example, some evidence that ondansetron might inhibit gut motility (Talley et al. 1990); thus, it is conceivable that ondansetron might have impaired the absorpt ion of alcohol into the bloodstream.”

“While this effect is consistent with data f rom animal studies suggesting that 5-HT3 receptor blockade can diminish the reinforcing properties of drugs … in the nucleus accumbens (Carboni et al. 1989; Wozniak et al. 1990; Yoshimoto et al. 1992), we could not exclude the possibility that ondansetron … alcohol.”

“ Ondansetron was found to augment certain stimulant, sedative, and discriminant effects of alcohol , without affecting psychomotor performance or alcohol pharmacokinetics.”

“The solubility of ondansetron also increased as the ethanol concentration increased.”

“Benzodiazepines, clomethiazole, tiagabine, vigabatrin, pregabalin, gabapentin, acamprosate, naltrexone, GHB, topiramate, ondansetron and baclofen at low dose (≤1 mg/kg, the dose range used in randomized trials in humans: 30 and 60 mg/day) have all been shown to at best reduce motivation to consume alcohol in rats.”

“Considering these antecedents, we explored modulation of the acute stimulating effect of ethanol (2.5g/kg) by two anxiolytic drugs, Mianserin (2.5 or 5mg/kg) and Ondansetron (1 or 3mg/kg).”

“In addition, ondansetron (1.0 mg/kg, subcutaneously) given before ethanol injection on days 1, 4, 7, and 10 significantly blocked the development (days 1, 4, 7, and 10), and expression (day 15) of sensitization to the locomotor stimulant effect of ethanol injection.”

“Results indicated that ondansetron (0.25–1.0 mg/kg, subcutaneously) given before the challenge dose of ethanol (2.4 g/kg, intraperitoneally) injection, significantly and dose dependently attenuated the expression of sensitization.”

“Acute administration of ondansetron (0.01 and 0.1 mg/kg) reduced ethanol intake in male Wistar rats by 35%, whilst water intake was unaffected.”

“The effect of 2.0 g/kg of EtOH was reduced by ON (0.1 mg/kg and 1.0 mg/kg sc) and, to the lesser extent and only in limited dose range (0.01 mg/kg) by TR.”

“Tropisetron (but not ON ) increased concentrations of EtOH in the blood.”

“ Ondansetron also modulates the toxicities of ethanol in the stomach and this action is likely to be mediated through the preservation of GMBF.”