Opioids

Population Pharmacokinetics to Support Intravenous and Enteral Methadone Dosing in Children

Posted on by Jeannine Sato

Journal of Clinical Pharmacology, January 2026

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Watt KM, Thompson EJ, Lam L, Zimmerman K, Hornik CP, Atz AM, Fernandez A, Hupp SR, Bhatt-Mehta V, Benjamin DK Jr, Anand R, Cohen-Wolkowiez M, Gonzalez D, Smith PB, Capparelli EV; Best Pharmaceuticals for Children Act — Pediatric Trials Network Steering Committee.

Methadone is used in hospitalized children to treat pain and iatrogenic opiate withdrawal. Optimal pediatric dosing for both enteral and intravenous methadone is unknown. We conducted two prospective, multi-center, open-label studies to characterize the pharmacokinetics of methadone in the pediatric population. 

Trends in Gabapentin Use in Neonatal Intensive Care Units from 2005 to 2020

Posted on by Kayla Korzekwinski

American Journal of Perinatology • November 2024

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Roberts AG, Kilpatrick R, Diaz LD, Benjamin S, Espinoza Santiago AJ, Jallow B, Monteith MF, Rumsey S, Clark RH, Zimmerman K, Benjamin DK Jr, Greenberg RG

This study aimed to analyze trends in gabapentin use in neonatal intensive care units (NICUs) and examine demographic characteristics, diagnoses, and concomitant medications associated with its use. Gabapentin use was rare but increased over time despite limited research on its safety and efficacy in infants, illuminating the need for further studies.

Use of physiologically-based pharmacokinetic modeling to inform dosing of the opioid analgesics fentanyl and methadone in children with obesity

Posted on by Kayla Korzekwinski

CPT: Pharmacometrics & Systems Pharmacology • June 2022

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Gerhart JG, Carreno FO, Ford JL, Edginton AN, Perrin EM, Watt KM, Muller WJ, Atz AM, Al-Uzri A, Delmore P, Gonzalez D; on behalf of the Best Pharmaceuticals for Children Act – Pediatric Trials Network Steering Committee
Children with obesity are commonly prescribed the opioids fentanyl and methadone, and accurate dosing is critical to reducing the risk of serious adverse events associated with overexposure. However, there is limited information to guide fentanyl and methadone dosing in these children. This study addresses the clinical knowledge gap using physiologically-based pharmacokinetic models of fentanyl and methadone developed in adults and scaled to children with and without obesity to explore the interplay of obesity, age, and pharmacogenomics.

CYP2B6 Genotype Affects Methadone Disposition in Children as Demonstrated by Physiologically-Based Pharmacokinetic (PBPK) Modeling

Posted on by Kayla Korzekwinski

Clinical Pharmacology and Therapeutics • March 2020

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Gerhart JG, Edginton A, Watt KM, Cohen-Wolkowiez M, Harper B, Muller W, Delmore P, Atz A, Gonzalez D; on behalf of the Best Pharmaceuticals for Children Act – Pediatric Trials Network Steering Committee

Meeting abstract from Annual Meeting of the American-Society-for-Clinical-Pharmacology-and-Therapeutics on March 18-21, 2020.

Dosing of Continuous Fentanyl Infusions in Obese Children: A Population Pharmacokinetic Analysis

Posted on by Kayla Korzekwinski

The Journal of Clinical Pharmacology • December 2019

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Maharaj AR, Wu H, Zimmerman KO, Speicher D, Sullivan JE, Watt K, Al-Uzri A, Payne E, Erinjeri J, Lin S, Harper B, Melloni C, Hornik CP; on behalf of the Best Pharmaceuticals for Children Act-Pediatric Trials Network Steering Committee
The impact of childhood obesity on fentanyl PK is relatively unknown. We developed a population pharmacokinetic (PopPK) model using opportunistically collected samples from a cohort of predominately obese children receiving fentanyl per the standard of care. Use of an allometric relationship between weight and clearance was appropriate for describing the PK of intravenous fentanyl in our cohort. Our proposed model-derived continuous infusion strategy maximized the probability of achieving target steady-state concentrations in children of varying weights.

Medication Use in the Neonatal Intensive Care Unit and Changes from 2010 to 2018

Posted on by Kayla Korzekwinski

The Journal of Pediatrics • January 2022

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Stark A, Smith PB, Hornik CP, Zimmerman KO, Hornik CD, Pradeep S, Clark RH, Benjamin DK, Laughon M, Greenberg RG.

The goal of this study was to provide up-to-date medication prescribing patterns in US neonatal intensive care units (NICUs) and to examine trends in prescribing patterns over time. The most frequently prescribed medications included ampicillin, gentamicin, caffeine citrate, poractant alfa, morphine, vancomycin, furosemide, fentanyl, midazolam, and acetaminophen. Of the top 50 medications used in infants with extremely low birth weight, only 20 (40%) are FDA-labeled for use in infants. Trends of medication use in the NICU change substantially over time. It is imperative to identify changes in medication use in the NICU to better inform further prospective studies.