The present study aimed to test the effect of grass jelly (Mesona palustris BL) and other ingredients effervescent powder (EV) on the blood glucose level and histology of pancreas in rats with diabetes mellitus induced by alloxan (DMIA rats). DMIA rats were orally administered with effervescent powder at dose 126 mg/ 200 g body weight (bw) (EV1), 252 mg/200 g bw (EV2) and 378 mg/200 g bw (EV3) for 4 weeks. The result showed after administration of EV to the DMIA rats, the blood glucose levels was significan