Inhibition of normal growth by chronic administration of delta-9-tetrahydrocannabinol.

Body weight, food and water intake, and feces weight of 20 albino rats were recorded daily for 70 days. On days 11 to 40, 12 rats received behaviorally effective doses of Delta-9-tetrahydrocannabinol, either orally or intraperitoneally. These rats ate significantly less than placebo-dosed controls during the treatment period, and gained significantly less weight. Food intake recovered in the 30-day posttreatment period, but the former drug group still weighed less than the controls on day 70. In addition, all rats who had received intraperitoneal injections of Delta-9-tetrahydrocannabinol showed evidence of chronic diffuse nonsuppurative peritonitis.