Chronic lithium treatment and dopamine-mediated behavior.

The effect of 3--4 weeks of chronic lithium (Li) treatment in food on amphetamine-induced stereotypy, hyperactivity, and hypothermia was examined. The long-term Li treatment failed to inhibit these behaviors and even resulted in small but statistically significant potentiation of stereotypy and hypothermia. The absence of an inhibitory effect of Le on these dopaminergic processes is consistent with Li's lack of antischizophrenic properties. Previous studies reporting conflicting results, including lithium inhibition of amphetamine-induced hyperactivity, used acute or very short-term lithium administration and/or did not verify serum lithium levels to be at therapeutically equivalent levels.