Characterization of Severe Adverse Drug Reactions at a Free-Standing Children's Hospital.

We performed a retrospective chart review on severe adverse drug reactions (ADRs) detected by a pharmacovigilance program at a free-standing pediatric hospital from January 2011 through September 2014. The pharmacist-led program identifies ADRs using electronic medical record triggers. A systematic approach was used to classify ADR type and severity and assure accurate documentation. Data collection included demographics, implicated medication, type of ADR, Naranjo probability scale, ADR-associated International Classification of Diseases, 9th Revision E codes, 30-day mortality, and health care visit cost. One hundred sixty-six severe pediatric ADRs were included, occurring in 163 unique patients. Severe ADRs were commonly associated with antimicrobials (48%), antineoplastics (10%), and antiepileptics (10%). The majority of ADRs were classified by the Naranjo probability scale as probable (59%). One hundred fifty-four patients were admitted to the hospital, with a median length of stay of 3 days; 22 of these patients required admission to the pediatric intensive care unit for a median of 3 days. The median estimated health care cost associated with severe ADRs was $4055.52. No deaths occurred. Nearly 40% of severe ADRs would have gone unidentified using ADR-associated International Classification of Diseases, 9th Revision E codes alone. The impact of pediatric ADRs on the health care system is underestimated. Strategies such as active pharmacovigilance programs enhance the identification, characterization, and documentation of these otherwise unrecognized ADRs.