An enteral nutrition preparation appeared recently on the Spanish market specifically for diabetic patients. It is a normocaloric and normoproteic formula of low osmolarity, rich in soluble fibre and slow-absorption carbohydrates such as fructose and starch, following the classic norms of the American Diabetics Association. The glycemic response was examined at 0, 30, 60 and 120 minutes following the ingestion of 250 cc of Precitene Diabet as breakfast for 40 diabetic patients, half treated with oral antidiabetic substances (DMado) and the other half with insulin (DMins). In both groups, the greatest glycemic increase was at 60 minutes. In the DMado patients, the increase at 60 minutes (70 mg/dl) was not significantly different from that considered by Skyler as acceptable. The same occurred at 120 minutes (40 mg/dl). In the DMins patients, the glycemic increase at 60 minutes was 27 +/- 29 mg/dl, more than that considered acceptable by Skyler (p 0.0006). After 120 minutes this difference was also greater than the acceptable level, by 41 +/- 38 mg/dl (p 0.0002). In conclusion, it may be considered that, for DMado patients, glycemic control remains within the postprandial limits considered to be "acceptable" so that no treatment modification is felt necessary in the administration of enteral nutrition with Precitene Diabet. The glycemic response in the DMins patients was higher than "acceptable", calling for rapid insulin supplements to their habitual NPH insulin doses.