Quinine as a potential tracer for medication adherence: A pharmacokinetic and pharmacodynamic assessment of quinine alone and in combination with oxycodone in humans

Shanna Babalonis, Aidan J. Hampson, Michelle R. Lofwall, Paul A. Nuzzo, Sharon L. Walsh

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

Effective strategies to monitor pharmacotherapy adherence are necessary, and sensitive biological markers are lacking. This study examined a subtherapeutic dose of quinine as a potential adherence tracer. Primary aims included examination of the plasma and urinary pharmacokinetic profile of once-daily quinine; secondary aims assessed pharmacokinetic/pharmacodynamic interactions with oxycodone (a CYP3A and CYP2D substrate). Healthy, nondependent opioid users (n = 9) were enrolled in this within-subject, double-blind, placebo-controlled inpatient study. Participants received the following oral doses: day 1, oxycodone (30 mg); days 2-4, quinine (80 mg); day 5, quinine and oxycodone (2 hours postquinine). Blood and 24-hour urine samples were collected throughout the study, and pharmacodynamic outcomes were assessed during experimental sessions (days 1, 4, 5). Quinine displayed a plasma Tmax ∼2 hours and t1/2 ∼10 hours. Oxycodone and noroxycodone parameters (Tmax, Cmax, t1/2) were similar with or without quinine present, although drug exposure (AUC) was slightly greater when combined with quinine. No pharmacodynamic interactions were detected, and doses were safely tolerated. During washout, quinine urinary concentrations steadily declined (elimination t1/2 ∼16 hours), with a 94% decrease observed 72 hours postdose. Overall, low-dose quinine appears to be a good candidate for a medication additive to monitor adherence for detection of missed medication.

Original languageEnglish
Pages (from-to)1332-1343
Number of pages12
JournalJournal of Clinical Pharmacology
Volume55
Issue number12
DOIs
StatePublished - Dec 1 2015

Bibliographical note

Publisher Copyright:
© 2015, The American College of Clinical Pharmacology.

Keywords

  • adherence
  • human
  • oxycodone
  • pharmacokinetic
  • quinine
  • tracer

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)

Fingerprint

Dive into the research topics of 'Quinine as a potential tracer for medication adherence: A pharmacokinetic and pharmacodynamic assessment of quinine alone and in combination with oxycodone in humans'. Together they form a unique fingerprint.

Cite this