Effects of chronic haloperidol treatment on ingestive behaviour and body weight regulation in the rat.

This study was designed to investigate the effects of two doses of haloperidol on body weight, food spillage and food and water intake using rats as subjects. In the first experiment, 12 male Wistar albino rats were observed in individual cages for 30 days, six receiving a daily injection of haloperidol (1 mg/kg IP in 1 ml/kg isotonic saline), while the other six received a control injection of isotonic saline in the experimental phase. In the second experiment, 12 rats were observed for 9 days in individual cages, six receiving a daily injection of 10 mg/kg haloperidol in 4 ml/kg isotonic saline in the experimental phase. In both studies, haloperidol depressed food intake and food spillage. With the lower dose of haloperidol (1 mg/kg), body weight was not depressed until several days after a significant reduction of food intake had been recorded. With the higher dose (10 mg/kg), body weight was depressed during the first 24 h, but quickly returned to normal, although food intake remained depressed. It is suggested that haloperidol may have a limited facilitatory effect on body weight.