Fenmetozole (Tosylate)

Fenmetozole Tosylate is an antagonist of the actions of ethanol, also antagonizes α2-adrenergic receptor, and acts as an antidepressant drug. In Vitro: Fenmetozole acts as an antagonist of α2-adrenergic receptor^[3]. In Vivo: In mice, fenmetozole antagonizes both the ethanol induced increase in locomotor activity at 2.0 g/kg and the decrease caused by 4.0 g/kg. Moreover, fenmetozole attenuates the ethanol-induced reduction in cerebellar cyclic guanosine monophosphate content, but it significantly elevates cGMP levels in this tissue. Fenmetozole does not change ethanol induced increases in punished drinking in a conflict test, but when given at a high dose, fenmetozole decreases both punished and unpunished responding. Fenmetozole fails to precipitate ethanol withdrawal-like reactions when it is given to physically-dependent, intoxicated rats. Fenmetozole (15-30 g/kg) reduces ethanol-induced impairment of the aerial righting reflex without altering blood or brain ethanol content^[1]. Fenmetozole alone has no ffect on punished drinking and does not alter ethanol action in the paradigm except at the highest dose tested (30 mg/kg) in rats^[2].