Background: Parenteral nutrition is used when the patient is unable to get regular feeding. Despite existing benefits, Some negative impacts Such as increased serum ammonia level after parenteral aminoacid solution might be involved in this method.

This study is amed to evaluate the liver enzyme and urea levels before and after aminoacid solution treatment among neonates admitted in Ali-Asghar Hospital.

Materials and methods: With a cross-sectional design, participants were 60 neonates admitted to Ali Asghar hospital NICU received parenteral nutrition between July 2010 And July 2011. Demographic and paraclinical data including age, sex, wt, serum ammonia; Bun; Cr, AST and ALT before and after treatment were recorded.

Results: Significant differences between the mean values of serum ammonia before and after treatment were seen (p=0.02). Mean values of serum urea showed significant differences before and after treatment as well (p=0.05). Mean values of liver enzymes after parenteral nutrition was not abnormal.

Conclusion: Our results show significant increasing in serum urea and ammonia after aminoacid solutio usage among the participants.