The effect of the synthetic cannabinoid receptor agonist, (-)11-hydroxy-Delta(8)-tetrahydrocannabinol-dymethylheptyl (HU 210), on rat body weight and eating and drinking behaviour was examined. In Experiment 1, the drug (25, 50 or 100 microg/kg), sub-chronically administered for 4 days, produced a dose- and time-dependent loss of body weight that, at the highest dose, was not regained by 7 days after the drug was stopped, and remained markedly below that of vehicle-treated animals. In Experiment 2, food and water intakes, which were evaluated in fasted rats, tested as in Experiment 1, were significantly inhibited only by the dose of 100 microgram/kg, and this effect was still present 7 days after the last injection of the drug. The possibility that the effects observed are not directly dependent on the control of appetite and might be ascribable to stress-related phenomena is discussed.