Lithium, a drug of choice in bipolar affective disorders, also affects the metabolism and cell proliferation in a diverse array of organisms. In this study, investigated the effect of lithium on bombesin-mediated function in excretion and growth of the pancreas and the salivary glands. The eight, protein content, amylase concentration and salivary flow rate of the pancreas, parotid and the submandibular glands ere determined in male Wistar rats after consumption of either water or lithium chloride (600 mg/I) for 14 days and each group received s.c. injection of either saline or bombesin (10 ųg/kg) during the last 4 days of experiment. Our results revealed that administration of bombesin in lithium-treated group not only suppressed pancreas and parotid eight augmentation due to bombesin, but also significantly decreased pancreas growth. Chronic lithium consumption significantly inhibited the protein content augmentation due to bombesin in the salivary glands. Getting bombesin, as ell as saline in lithium-treated group, resulted in notable decrease in salivary protein content. Protein content of pancreatic gland increased considerably in the bombesin-injected groups either treated with saline or lithium. In conclusion, the stimulator effect of bombesin on the growth and protein content of the pancreas and the salivary gland as inhibited b lithium. Lithium seems to be a potent inhibitor of growth factors induced by bombesin probably through inhibiting phosphatidylinositol 4, 5, bisphosphate hydrolysis.