Alprazolam dependence in mice.

Mice were treated with 0.025% alprazolam incorporated into their laboratory chow for periods of one, two, and four weeks. Treated animals gained weight and appeared healthy during treatment, although an increased number of animals were lost in the treatment groups due to cannibalism. When regular food was substituted, alprazolam-treated animals experienced a withdrawal reaction qualitatively similar to that previously observed following similar lengths of treatment with 0.1% diazepam in food. The withdrawal reaction following alprazolam had a faster onset and a shorter time course, and was less intense. In a separate experiment, eight mice were treated with alprazolam for two weeks but were housed singly. This eliminated the cannibalism problem and no animals were lost during the treatment phase; the withdrawal syndrome was similar to that seen in group-housed animals. The model of benzodiazepine dependence in mice would appear to generalize to the entire class of drugs and may permit distinctions to be made between the time-course of withdrawal reactions between the various members of that class.