Objective: To compare use of standard enteral formula versus enteric formula with prebiotic content in terms of nutrition therapy related outcomes among neurocritical care patients., Methods: A total of 46 adult neurocritical care patients who received nutrition therapy with standard enteral formula (SEF group; n = 23) or enteral formula with prebiotic content (EFPC group; n = 23) during their hospitalization in intensive care unit (ICU) were included in this prospective randomized controlled study. Data on patient demographics (age, gender), diagnosis, co-morbid diseases, anthropometrics, length of stay (LOS) in hospital and ICU, Nutritional Risk Screening (NRS-2002) score, and Acute Physiology and Chronic Health (APACHE-II) score were recorded at enrollment. Data on daily nutritional intake [total energy (kcal/day), carbohydrate (g/day), protein (g/day), lipid (g/day), FOS (g/day), enteral volume (ml/day), fluid in enteral product (ml/day) and fluid intake (ml/day)], achievement of target dose [total fluid intake in enteral product (ml)/20 h], laboratory findings (blood biochemistry and complete blood count), complications and drug treatments were recorded on Day 1, Day 4, Day 7, Day 14 and Day 21 of nutrition therapy in SEF and EFPC groups., Results: Use of EFPC compared to SEF was associated with significantly higher total energy, carbohydrate, protein, lipid, enteral volume and fluid intake (p values ranged from <0.05 to <0.001) on each day of nutrition therapy. Target dose was achieved by majority of patients (86.9%) and at day 4 of nutrition therapy in most of patients (71.7%) in the overall study population. Patients in the EFPC group had a non-significant tendency for higher rate (95.7% vs. 78.3%) and earlier (87.0% vs. 56.5% on day 4) achievement of target dose, lower rate (8.7% vs. 56.5%) and faster amelioration (none vs. 52.2% were diarrheic on day 7) of diarrhea and lesser need for insulin (56.5% vs. 13.0%, p = 0.002). Nutrition therapy was associated with significant decrease in prealbumin (Day 14 vs. Day 1, p < 0.05 for both), albumin (Day 14 vs. day 1, p < 0.01 for SEF, p < 0.05 for PEF), hemoglobin (Day 14 and Day 21 vs. Day 1and Day 14 vs. Day 4, p < 0.001 for each for SEF, Day 7, Day 14 and Day 21 vs. Day 1, p < 0.01 for each for PEF) and hematocrit (Day 14 and Day 21 vs. Day 1, p < 0.001 for each for both) levels in both SEF and EFPC groups., Conclusions: In conclusion, our findings revealed achievement of target nutritional intake in majority of neurocritical care patients via nutrition therapy, whereas EFPC was associated with a non-significant tendency for more frequent and earlier achievement of target dose along with significantly lower rate and faster amelioration of diarrhea as compared with SEF group. Prealbumin and albumin levels remained below the normal range, whereas C reactive protein (CRP) and white blood cell (WBC) were over the normal range throughout the nutrition period in both groups, while creatinine and urea levels were higher in EFPC than in SEF group. Hence, our findings seem to emphasize the importance of avoiding protein debt in provision of nutrition therapy and the likelihood of deterioration of nutritional status in elderly neurocritical care patients despite provision of early enteral nutrition support due to complex and deleterious inflammatory and metabolic changes during critical illness., (Copyright © 2018 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)