The main objective of the present study was to investigate the use of drugs in the pediatric intensive care units (PICUs) at a pediatric hospital. Data were equally collected from charts of PICUs of the Hospital del Niño DIF, Pachuca, Hidalgo, Mexico in 2007. The data included demographic, clinical data and those on drugs usage. A total of 45 patients were included at the study, all (100%) of whom received one or more drugs. Data were collected and 57 different drugs were given to the pediatric patients. The median number of drugs/inpatient was 6.9 (1-17). The therapeutic class most prescribed was anti- infective (30.6 % of all the prescriptions), followed by electrolytes (13.3 % of all the prescriptions) and gastrointestinal agents (12.9 % of all the prescriptions). KCI was the drug most commonly used (64.4 % of all the patients) followed by ranitidine and amikacin (both with 51.1 % of all the patients). As in many studies, the therapeutic class most used was the anti-infectives. Substantial variation exists in hospitalists' reported management of common pediatric conditions. To decrease undesirable variation in care, a stronger evidence base for inpatient pediatric care must be built.