Children with medical complexity (CMC) often require multiple medications, leading to polypharmacy, which seems to be linked to adverse effects, administration errors, and increased caregiver burden. This study aimed to describe the prevalence of polypharmacy, medication burden, off-label drug use, and associated costs. Conducted at the Pediatric Palliative Care Center of Padua, Italy, from August to October 2021, this cross-sectional observational study included patients up to 23 years old with at least one prescribed drug. Data were collected from medical records and caregiver interviews. Drug costs were collected from the Italian Medicine Agency. Descriptive statistical analysis was performed. For comparisons among categorical variables, the Chi-square test was used, and for those among continuous variables, the ANOVA test was used. This study analyzed treatment regimens of 169 patients with a median age of 12.5 years (0.3-23). Polypharmacy was present in 52.7% of patients, and medication burden was observed in 44.4%, both varying significantly by primary diagnosis (p < 0.001). The median daily cost per patient was EUR 2.2 (IQR 0.9-7.1), with significant variation among subgroups. Only 34.6% of prescriptions were off-label. polypharmacy and medication burden are frequent among our CMC population, with some differences according to primary diagnosis.