EXPERIMENTAL STUDY FOR SIDE EFFECTS OF METHYLENE BLUE

Abstract

The experimental study on the acute toxicity of methylene blue was done for the purpose of comfirming the safety of endoscopic dying. Previous papers reported that the methylene blue showed no significant side effect without direct toxic effect on nerve fibers in cases of intrathecal instillation, and was considered safe enough for oral administration. This study was attempted to know the influence of methylene blue to the liver and kidney. Wister rats, weighing 150 gr. each, were given 10, 50 or 100mg/kg of methylene blue I.P. or P.O.. Twenty four hours after administration, the rats were killed. The blood samples were measured for GPT, ALP and total bilirubin, and the liver and kidney were examined histologically. Some of the rate, mainly in the large dosage groups, showed the slightly elevated GPT level, spotty necrosis of the liver cell, and slight damage of the glomeruli and tubules in the kidney. These results may suggest a possibility of side effects caused by oral administration of methylene blue in a large dose.