Acetaminophen and Acetaminophen-Opioid Combination Prescribing Trends Among Hospitalized Children, Adolescents, and Young Adults with Cancer.

Acetaminophen (APAP) is a ubiquitous antipyretic and analgesic used in children in the United States (US), including those with cancer. The effects of US Food & Drug Administration (FDA) guidance on APAP prescribing have been described for healthy adults and children; however, APAP use patterns in neonates, infants, children, adolescents, and young adults (CAYA) with cancer are unknown. Considering their increased risk of liver injury, APAP's potential for causing hepatoxicity, and FDA guidance changes, this study examined the recent evolution of APAP use in CAYA with cancer. This retrospective, multi-center analysis extracted APAP prescribing data from the Pediatric Health Information System® (PHIS). Eligible patients were aged 0-26 years, had a cancer diagnosis per International Classification of Diseases (ICD) codes, and were prescribed a chemotherapeutic. APAP and APAP-opioid combination prescribing were assessed at hospital, regional, and national levels. APAP and APAP-opioid combination use changes were assessed using the non-parametric Mann-Kendall test. PHIS records for the complete years of 2004-2021 yielded 388,364 inpatient encounters for 50,779 unique patients. Of these, 87.3% of patients received APAP. Although APAP-opioid combination use was infrequent overall, CAYA receiving APAP were more likely to receive APAP-opioid combination medications (N=25,880, 13.4%, p < 0.001) compared to those not receiving APAP. Among specialty children's hospitals, national APAP use was stable over the study period. Regionally, APAP use increased among Northeastern hospitals. APAP-opioid combination use decreased nationally with regional variation. In contrast to the steady decline in other regions, Southern APAP-opioid combination use was consistently elevated before declining in 2014.