Diabetic gastroparesis. A critical reappraisal of new treatment strategies.

Delayed gastric emptying, gastroparesis, is one of the sequelae of diabetes mellitus. Symptoms may include postprandial nausea, epigastric pain, bloating, vomiting, early satiety and unpredictable blood sugar fluctuations. Nowadays diagnosis is made by the measurement of gastric emptying with a radionuclide test meal. Using this technique some 50% of diabetic patients show signs of disordered gastric emptying. Relief is best delivered by agents promoting gastric emptying. In phase II single-dose studies metoclopramide, domperidone, cisapride, erythromycin and renzapride were all able to enhance gastric evacuation of solid and liquid meals in patients with diabetic gastroparesis. A few short term studies support the efficacy of domperidone and renzapride, but long term trials are lacking. Erythromycin, mimicking the potent gastrokinetic effect of motilin, may hold considerable promise for the future. Experience with erythromycin in diabetic gastroparesis is nonetheless very limited. To some extent the therapeutic effectiveness of metoclopramide and cisapride has been established in placebo-controlled trials. In trials with a placebo-controlled crossover design, however, only metoclopramide showed a sustained positive effect. Metoclopramide, which combines gastrokinetic and antiemetic properties seems, so far, the best therapeutic option in diabetic gastroparesis. Cisapride may be considered as a good alternative in cases where limited efficacy or side effects preclude the use of metoclopramide.