OBJECTIVE: Safety and intestinal tolerance of an early high-dose enteral administration of antioxidative vitamins, trace elements, and glutamine dipeptides. DESIGN: open intervention trial. SETTING: Two university teaching hospitals. PATIENTS: A total of 14 patients requiring jejunal feeding (64+/-14 y). INTERVENTION: A measure of 500 ml/day Intestamin (FreseniusKabi: 250 kcal/1.050 kJ, 300 microg selenium, 20 mg zinc, 400 mug chromium, 1500 mg vitamin C, 500 mg vitamin E, 10 mg beta-carotene, 30 g glutamine) for 5 days beginning 6 h after surgery. Parenteral/enteral nutrition was provided to achieve energy target (25 kcal/kg/day). ASSESSMENTS: Intestinal complaints, plasma nutrients, and glutathione. RESULTS: Only minor signs of nausea, hiccups, flatulence (3/14). Plasma micronutrients (except beta-carotene) postoperatively decreased and increased to normal on day 5. Extracellular glutamine remained low (preop: 520+/-94; d1: 357+/-67; d5: 389+/-79 micromol/l); total glutathione decreased (d1: 9.4+/-3.8; d5: 3.6+/-2.5 micromol/l). CONCLUSION: Study feed is well tolerated and metabolically safe representing a valuable tool for targeted pharmaconutrient supply.