The effect of lithium on food intake in rats.

The influence of lithium on ingestive behavior and body weight was studied in male and female rats. Single i.p. doses of LiCl (3.6-7.2 mmol/kg) reduced both food intake and water consumption. Repeated large doses of LiCl given intraperitoneally caused a prompt anorexia and delayed polydipsia as well as weight loss, effects that were much more pronounced in male than in female rats. Small doses of LiCl on the other hand, increased food intake and body weight during long-term treatment. The findings indicate that an increase in food intake can account for the increased body weight sometimes seen in rats given lithium.