Dexmedetomidine alleviates ethanol withdrawal symptoms in the rat

The effect of dexmedetomidine, a selective alpha(2)-adrenoceptor agonist, on ethanol withdrawal symptoms was studied in chronically ethanol-fed rats. After a 4-day ethanol intoxication period the rats were given sc injections of dexmedetomidine (3, 10, or 30 mu g/kg) or saline (control group) at 10, 16, 22, and 39 h after the last dose of ethanol. The severity of ethanol withdrawal symptoms (rigidity, tremor, irritability, hypoactivity) was rated up to 58 h, blind to the treatments. The results showed that dexmedetomidine at doses 10 and 30 mu g/kg significantly diminished the severity of the ethanol withdrawal reaction as measured by the sum score of the three most specific withdrawal signs (rigidity, tremor, and-irritability). Dexmedetomidine at 10 mu g/kg was the most effective dose, especially in the latter half of the withdrawal period (23-58 h after last dose of ethanol). The results suggest that dexmedetomidine in the treatment of ethanol withdrawal symptoms should be further studied. (C) 1997 Elsevier Science Inc.