Glutamine-induced recovery in intestinal barrier function by reducing bacterial translocation was demonstrated in previous studies. In this trial, intensive care unit patients with enteral feeding will receive either enteral glutamine or maltodextrin as placebo for 10 days and the effects of the intervention on intestinal permeability will be assessed.

A randomized, double blind, controlled trial will be conducted in general intensive care unit (ICU) in Tehran, Iran. After a full review of the inclusion and exclusion criteria and explanation of the risks and benefits of the study, written consent form will be completed. The participants are 60 eligible hospitalized patients with enteral feeding in ICU, aged ≥ 18 years. Intervention patients will be received 0.3 g/kg/day of glutamine along with enteral formula for 10days and control patients will be received maltodextrin along with enteral formula for 10 days. Patients will be evaluated for plasma endotoxin and plasma zonulin.

Inclusion Criteria:

• Adult patients (>18 years old) admitted to ICU
• Start of study intervention within 48 hours after ICU admission
• Expected to require enteral nutrition for at least 72 hours aiming for full enteral nutrition and receive at least 80 percent of enteral formula during the first 48 hour
• Written informed consent of patient or written informed consent of legal representative

Exclusion Criteria:

• Enrollment in a related ICU interventional study
• Requiring other specific enteral nutrition for medical reason
• Death or Discharge before 5th day
• Having any contra-indication to receive enteral nutrition
• Pregnant patients or lactating with the intent to breastfeed
• BMI <18 or > 40.0 kg/m2
• Have life expectancy of <6 mo
• Patients who are moribond
• Liver cirrhosis- Child's class C liver disease
• Have seizure disorder requiring anticonvulsant
• History of allergy or intolerance to the study product components
• Receiving glutamine during two weeks before start study product
• Have other reasons