• Journal Article

Excretion of Methadone in Sweat of Pregnant Women Throughout Gestation After Controlled Methadone Administration

Citation

Barnes, A. J., Brunet, B. R., Choo, R. E., Mura, P., Johnson, R. E., Jones, H., & Huestis, M. A. (2010). Excretion of Methadone in Sweat of Pregnant Women Throughout Gestation After Controlled Methadone Administration. Therapeutic Drug Monitoring, 32(4), 497-503.

Abstract

Sweat patches (n = 350) were collected throughout gestation from 29 opioid-dependent pregnant women participating in an outpatient methadone-assisted therapy program. Volunteers provided informed consent to participate in institutional review board-approved protocols. Methadone was eluted from sweat patches with sodium acetate buffer, followed by solid-phase extraction and quantification by gas chromatography mass spectrometry (limit of quantification >= 10 ng/patch). Methadone was present in all weekly patches (n = 311) in concentrations ranging from 10.2 to 12,129.7 nanograms per patch and in 92.3% of short-term patches (n = 39, worn for 12 or 24 hours) in concentrations up to 3303.9 nanograms per patch. Correlation between patch concentrations and total amount of drug administered (r = 0.224), and concentrations and duration of patch wear (r = 0.129) were both weak. Although there were large intra-and intersubject variations in sweat drug concentrations, sweat testing was an effective alternative technique to qualitatively monitor illicit drug use and simultaneously document methadone medication-assisted treatment