Ten children who have a diffuse form of hyperinsulinism have been treated in our department by Sandostatine® given in three subcutaneous injections for several years, in order to avoid a sub-total pancreatectomy. The only possible adverse effect is the appearance of vesicular lithiasis which can be treated by ursodesoxycholic acid . We changed the Sandostatine® treatment of one of our patients by the Sandostatine® LP (retarded liberation form) after written consent of his two parents. Thus we could stop the three injections per day of Sandostatine®. Sandostatine® LP proved to be as efficient on hypoglycemias as the subcutaneous multi-daily injections (SC). The glycemia values were strictly normal, and no hypoglycaemia was observed. Following this observation, we propose to try to substitute the treatment of Sandostatine® given in several subcutaneous injections by one injection of Sandostatine® LP in 10 children followed in the department of Metabolism for hyperinsulinism.