Plasma Concentrations and Renal Clearance of Morphine, Morphine-3-Glucuronide and Morphine-6-Glucuronide in Cancer Patients Receiving Morphine

Andrew A. Somogyi, Roger L. Nation, Charles Olweny, Panagiotis Tsirgiotis, Jacoba van Crugten, Robert W. Milne, James F. Cleary, Catherine Danz, Felix Bochner

Research output: Contribution to journalArticleResearchpeer-review

44 Citations (Scopus)


The plasma concentrations and renal clearance values of morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) were determined in 11 adult cancer patients maintained on a long term oral morphine dosage (10 to 100mg every 4h). Concentrations in plasma and urine were determined by a specific high performance liquid chromatography assay. In this group of patients, whose creatinine clearance values ranged from 52 to 180 ml/min (3.12 to 10.8 L/h), average steady-state plasma concentrations of morphine, M3G and M6G were related (p < 0.01) to the morphine dose per kilogram of bodyweight. The mean total urinary recovery as morphine, M3G and M6G was 74.6 ± 26.5% of the dose. Renal clearance values for M3G and M6G were closely related (r2 = 0.80; p < 0.0005). It was not possible to detect a relationship between the renal clearance of morphine, M3G and M6G, and that of creatinine. The renal tubular handling of all 3 compounds showed wide interindividual variation, and there was evidence of either net renal tubular secretion or reabsorption. There was no apparent relationship between plasma morphine and M6G concentrations and pain relief.

Original languageEnglish
Pages (from-to)413-420
Number of pages8
JournalClinical Pharmacokinetics
Issue number5
Publication statusPublished - 1 Jan 1993

Cite this