Excretion of methadone in sweat of pregnant women throughout gestation after controlled methadone administration

摘要

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 GCMS (LOQ ≥10 ng/patch). Methadone was present in all weekly patches (N=311) in concentrations ranging from 10.2 to 12,129.7 ng/patch and in 92.3% of short-term patches (N=39, worn for 12 or 24 h) in concentrations up to 3303.9 ng/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 inter-subject variation in sweat drug concentrations, sweat testing was an effective alternative technique to qualitatively monitor illicit drug use and simultaneously document methadone medication assisted treatment.