Parenteral nutrition (PN) must be considered an intravenous medication, containing over 50 ingredients and additives. Thus, the stability of the final product is always under risk. PN can be received in two ways: from a ready-to-use bag or from an individually tailored bag, both in adults and in pediatric patients. Pediatric PN admixtures are more susceptible than adult PN admixtures due to their nature. Patients who receive PN often need to receive parenteral medications concomitantly, and separate administration is challenging most of the time. Here we report two problems with stability encountered with pediatric PN bags. In the first case, the main focus is on the compatibility of heparin with PN. Compatibility of the medications via the Y-site or a three-way stopcock must be examined in such cases. If the medication is incompatible with PN, administration via the Y-site or addition into the PN mixture should be avoided. Emulsion disruption caused by heparin is a known example of incompatibility for pediatric PN. In the second case, the main focus is on the additives and their amount in the pediatric PN mixture. Compounding pediatric PN is mixing numerous additives in a small volume, which results in a highly concentrated solution that often causes calcium–phosphate precipitation. This may lead to serious consequences, including death. All the possible causes of instability, even the temperature of the environment, must be considered. In pediatric PN solutions, the cooperation between physicians and pharmacists is necessary for maintaining safe nutritional treatment.

Keywords: Clinical nutrition, clinical pharmacy, drug administration, incompatibility, parenteral nutrition