Clenbuterol is known to increase muscle mass in nonburned and burn-injured subjects. The effects of clenbuterol on wound healing and the postburn response were examined in both nutritionally matched and free-feeding groups of rats. Rats received either a sham or 30% total body surface area scald burn and then a dorsal incision. Clenbuterol (2 mg/kg/day) was administered subcutaneously via a miniosmotic pump. The burn injury resulted in a sustained non-temperature-dependent hypermetabolism that was not altered by clenbuterol. Clenbuterol induced muscle anabolism and body growth in sham and burned-injured animals. Treated sham animals demonstrated increased wound breaking strength. Matched nutritional intake attenuated the body weight gain, although muscle anabolism was still evident in treated animals. Clenbuterol elevated RNA concentration in the tibialis muscle and reduced it in the liver. There was no statistical difference in wound strength when nutritional intake was matched. Clenbuterol's actions appear to be dependent on substrate availability. Clenbuterol may prove beneficial in patients with severe prolonged catabolic state, such as that associated with burn injury, by promoting protein anabolism and enhancing wound healing.