Taurine was given to mice: (i) intracerebroventricularly (i.c.v.) 20 min prior to 4.5 g/kg of ethanol intraperitoneally (i.p.); (ii) i.p. 10 min-5 days prior to ethanol; or (iii) orally (p.o.) as drinking fluid for 30 days prior to ethanol. Ethanol-induced sleeping time was increased by i.c.v. taurine and also by i.p. taurine when the pretreatment interval was 4-5 days. The long i.p. pretreatment time probably reflects the slow uptake of taurine by the brain. Sleeping time was decreased by p.o. taurine and by i.p. taurine when the pretreatment interval was 10-20 min. The mechanism of this attenuation remains unclear.