The effect of activated charcoal on mouse sleep times induced by intravenously administered hypnotics

The effect of orally administered activated charcoal (AC) on the sleep times of mice following intravenous injection of various hypnotics was investigated. Preliminary studies with phenobarbital (Pb) showed that a linear relationship exists between the Pb-induced sleep time and the logarithm of the Pb dose in both control and AC treated mice. Half-lives of Pb in the two groups were estimated to be 8.1 and 0.9 h, respectively. A linear decline in Pb-induced sleep time with increasing dose of AC was observed up to a maximum effective dose of AC beyond which dose increments caused no further reduction in sleep time. A similar relationship was observed between sleep time and the concentration of sodium sulfate in which the AC was suspended. AC treatment resulted in an 82-88 per cent reduction in sleep time induced by administration of phenobarbital, methyprylon, glutethimide, ethchlorvynol, and methaqualone. AC had no significant effect on sleep time following amobarbital or pentobarbital administration.