The aim of this study was to investigate whether a L-carnitine, choline, artichoke leaf extract and sorbitol combination (Hepabial Camitine (R)) supplied by drinking water would influence broiler performance under stress induced by high stocking density (18 chicks per square meter). A total of 270 1-day-old male broiler chicks (Avian Farm) were randomly distributed into 2 groups (Hepabial Camitine treatment group and Control group), each with 5 replicate groups containing 27 chicks, and were fed with standard broiler diets. Hepabial Carnitine (R), was added in drinking water of the treatment group at I mill beginning by day 35 (when the stocking density was over 30 kg total body weight/m(2)) until the slaughter of the animals at the 42(nd) day of the experiment. All chicks were individually weighed at hatching and thereafter on the 35(th) and 42(nd) days of the experiment. Body weight gain, feed intake and feed conversion ratio were determined on days 35 and 42. Carcass performance (hot carcass weight and hot carcass yield) was measured after slaughtering. Hepabial Carnitine (R) supplied by drinking water had no significant effect on body weight, body weight gain, feed intake and hot carcass yield of broilers. However, birds receiving Hepabial Carnitine (R) consumed less amount of feed (P=0.531) while gaining higher body weight (P=0.144) when compared with the control group. Feed conversion ratio was significantly improved (P < 0.05) with a Hepabial Carnitine (R) supplementation in drinking water. Similarly, hot carcass weight was found significantly higher (P < 0.05) in birds receiving Hepabial Carnitine (R) in comparison to the control group. It is concluded that L-carnitine, choline, artichoke leaf extract and sorbitoi combination (Hepabial Carnitine (R)) added in drinking water could improve performance of broilers under stress induced by high stocking density.