The pre-mixed $_{13}C$-urea powder preparation in ${Helikit}_{TM}$ for test of Helicobacter pylori was evaluated for pharmacological properties. The oral doses of the preparation used in mice were 30-fold as compared to human doses. The results obtained in the present study demonstrate that spontaneous movement, hexobarbital-induced hypnosis, rotarod performance, body temperature, acetic acid-induced writhing syndrome, chemical and electroshock convulsion, pupil size and intestinal propulsion had not been affected at the oral doses of 230, 700 and 2100 mg/kg in mice. The blood pressure was slightly elevated as given intravenously in rats at a dose of 5 mg/kg of the preparation, but respiration was not influenced at the dose. In isolated guinea pig ileum and rat fundus preparation, the preparation at a concentration of $1{ imes}10^{4}$ g/ml neither caused any direct effect nor inhibited the contraction produced by acetylcholine, histamine or 5-hydroxytryptamine. These results reported here provide evidence that pre-mixed $^{13}C$ 13/C-urea powder preparation is free of general pharmacological properties performed in oral administration.