Purpose of the present study was to investigate pharmacological and toxicological effects of gas plant. Aqueous extracts prepared from its leaves and fruits were tested on the guinea-pig skin by comparing with 2,4-dinitrochlorobenzene. When histopathological examination was made on guinea-pig skin injected with the extracts, there was no change observed in mast cells, but acute exudative inflammation and infiltration of polymorphonuclear leukocytes were noticed in the hypodermis. Their edema forming activities were also tested in the rat paw experiment and their effects were compared to those induced by formalin. In vivo bronchial tone/blood pressure and isolated ileum experiments in guinea-pigs were performed. Aqueous extracts prepared from this plant were found to cause bronchoconstriction and hypotension, which were not dose-dependent. They also elicited concentration-dependent contractions of the isolated guinea-pig ileum, which were not abolished by chlorpheniramine, ketotifen and dexamethasone. D. albus extracts had no significant effect on the mouse pain threshold in "Tail-clip" experiments. Their effects on the central nervous system were examined by using swimming endurance test and observational screening on mice. In this case, a sedative activity was observed. It was concluded that aqueous macerates from leaves and fruits of D. albus causes an acute phase inflammatory response.