D-002 is a natural mixture of higher aliphatic primary alcohols, isolated and purified from beeswax which has anti-inflammatory properties, reduces leukotrienes (LTB4) and thromboxane B2 (TXB2) in exudated carrageenan-induced pleurisy, and has anti-ulcer activity in different experimental models. This study was conducted to determine the effect of D-002 on the pre-ulcerative phase of carrageenan-induced colonic ulceration in guinea-pigs. Animals were randomly distributed among a negative control, a positive control group treated with the vehicle Tween 20 in H2O and two experimental groups receiving D-002 at 25 and 50 mg kg(-1). All treated animals received degraded carrageenan for three days for induction of colonic ulceration. Significant reductions in wet weight, wall thickness, counts of infiltrating polymorphonuclear neutrophils and of macrophages, and histological index were observed in colonic mucosa of D-002-treated animals compared with controls. It is concluded that D-002 has a protective effect on the pre-ulcerative phase of carrageenan-induced colonic ulceration in the guinea-pig.