ering a pharmaceutically effective amount of a deltorphin to said mammal.Preferably, the deltorphin is administered in a pharmaceutical composition at a dosage in the range of about 0.5 mg/kg body weight to about 20 mg/kg body weight, or alternatively lower doses in the range of about 1 .mu.g/kg body weight to about1000 .mu.g/kg body weight of the mammal.Preferably, the mammal is a human.DETAILED