Effects of flumazenil (Ro 15-1788, CAS 78755-81-4) on ethanol withdraw
al syndrome (EWS) has been investigated in rats. Behavioral EWS sympto
ms appeared during the first 6 h of ethanol withdrawal. Flumazenil (2.
5 and 10 mg/kg i.p.) ina eased horizontal and vertical locomotor activ
ity significantly and also precipitated abnormal gait and agitation at
the beginning of EWS in a dose dependent manner. However, thereafter
it reduced the severity of abnormal posture and gait, tail stiffness,
agitation and stereotyped behavior in a dose dependent manner. At the
6th hour of EWS, flumazenil (10 mg/kg) reduced total EWS score signifi
cantly, but shortened the latency of audiogenic seizures and increased
the severity of wet dog shakes. Flumazenil (2.5 and 10 mg/kg) did not
elicit behavioral EWS symptoms and audiogenic seizures in non-depende
nt (control) rats. It did not cause any significant change on locomoto
r activities in these groups. According to those results, certain acti
ons of flumazenil on the experimental EWS may suggest a potential bene
ficial effect of this drug in the treatment of EWS in alcoholics, but
its enhancing effects on some behavioral EWS symptoms mid a potential
proconvulsant activity may be a drawback for its use in the treatment
of EWS.