This study was carried out to evaluate the dose-effects of ingestion of Maharishi Amrit Kalash 5 (MAK 5), an Ayurvedic food supplement, on the immune function in 10 week female inbred BALB/c mice. Superoxide anion (O(2) ) production of peritoneal macrophages and the response of spleen cells to concanavalin A (Con A) were examined in mice given MAK 5 by gastric intubation of an aqueous emulsion at the doses of 10, 50, 100 and 200 mg/kg once a day for 20 days. Glucose consumption of peritoneal macrophages in the MAK 5-treated mice at all doses after 24 hours of incubation, and only at the dose of 200 mg/kg after 48 hours of incubation were significantly higher than those in the control group. O(2) production of peritoneal macrophages in the presence of stimulator was significantly higher in the MAK 5-treated group at the dose of 200 mg/kg than in the control group. Activities of β -glucuronidase and lactate dehydrogenase in the peritoneal macrophages were significantly increased in the MAK 5treated mice at all doses. MAK 5 did not enhance spontaneous splenic lymphocyte proliferation at any dose in mice. Stimulation indices in the MAK 5-treated groups at the doses of 50, 100 and 200 mg/kg were significantly higher than that of the control group. These results indicate that gastric intubation of MAK 5 once a day at the dose of 50 mg/kg enhances not only macrophage function but also lymphocyte responsiveness in mice.