@article{ref1,
title="Development of an improved method to estimate the days of continuous drug ingestion, based on the micro-segmental hair analysis",
journal="Drug testing and analysis",
year="2021",
author="Kuwayama, Kenji and Miyaguchi, Hajime and Kanamori, Tatsuyuki and Tsujikawa, Kenji and Yamamuro, Tadashi and Segawa, Hiroki and Okada, Yuki and Iwata, Yuko T.",
volume="ePub",
number="ePub",
pages="ePub-ePub",
abstract="To prove drug-related crimes, it is important to estimate the date on which a specific drug was ingested. Previously, we developed a method, &quot;micro-segmental hair analysis,&quot; to estimate the day of ingestion of a single-dose drug by segmenting a hair strand into 0.4-mm segments, which correspond to daily hair growth. In this study, the method was improved to estimate the days of continuous drug ingestion. The subjects ingested four hay-fever medicines (fexofenadine, epinastine, cetirizine, and loratadine) continuously (1-18 days) and chlorpheniramine as a single dose at intervals of several weeks as an internal temporal marker (ITM). The hair strands of the subjects were collected and subjected to a micro-segmental analysis. The distribution curves of each hay-fever medicine in a hair strand had broad peaks reflecting the number of days of drug ingestion. The positions on the curves corresponding to the first and final ingestion days of hay-fever medicines were identified using the ITM. The positions were near the hair segments on both ends of full width at half maximum (W(2) ) of the broad peak. When the first and final days of continuous ingestion were estimated using W(2) , independent of peak shape, the absolute average error from the actual ingestion days was approximately 2 days. Overall, we established a method to estimate the days of both single-dose and continuous drug ingestions. Furthermore, the method would be useful to investigate drug ingestion history in various scenes such as drug-related crimes and therapeutic drug monitoring.<p /> <p>Language: en</p>",
language="en",
issn="1942-7603",
doi="10.1002/dta.3025",
url="http://dx.doi.org/10.1002/dta.3025"
}