Case ReportMeropenem to Treat Valproic Acid IntoxicationSmolders, Elise J. PharmD, PhD*; Ter Heine, Rob PharmD, PhD*; Natsch, Stephanie PharmD, PhD*; Kramers, Kees MD, PhD† Author Information *Department of Pharmacy, Radboud Institute of Health Sciences, Radboud University Medical Center; and †Department of Pharmacology-Toxicology and Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands. Correspondence: Elise J. Smolders, PharmD, PhD, Department of Pharmacy, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands (e-mail: [email protected]). Therapeutic Drug Monitoring: June 2022 - Volume 44 - Issue 3 - p 359-362 doi: 10.1097/FTD.0000000000000973 Buy Metrics Abstract This therapeutic drug monitoring (TDM) grand round describes a patient with serious valproic acid intoxication. A total valproic acid level of 844 mg/L and an unbound valproic acid level of 604 mg/L were observed. Meropenem was administered to enhance the clearance of valproic acid. This off-label usage of meropenem is based on the drug–drug interaction between carbapenems and valproic acid, which reduced the level of valproic acid within 24 hours after administration. Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.