Analysis of Ofloxacin in Hair as a Measure of Hair Growth and as a Time Marker for Hair Analysis

Using ofloxacin as a time marker in hair analysis for monitoring the dosage history of haloperidol

“…We have previously shown that the antimicrobial, ofloxacin, is excreted into hair, and that hair growth rate can be determined by the outward movement of the part of the hair containing the drug [12][13][14][15]. In the present study, we show that by combining analysis of haloperidol and ofloxacin from a single hair shaft, ofloxacin can be used as a time marker to determine the dosage history of haloperidol in an individual patient.…”

“…We have shown that an ingested drug, whether administered continuously or intermittently, is deposited in hair in proportion to the dose and that it is captured there, moving outwards along the shaft as the hair grows [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Therefore, it may be possible to consider a strand of hair as a "tape-recorder," which continuously stores all the data about the drug exposure of individual over the past several months, or possibly years.…”

“…However, this "tape-recorder" has its own "tapespeed", which corresponds to the growth rate of each hair, and which is variable both between and within subjects [15,24]. In addition, each hair has its own growth cycle of about 2 to 8 years or more [25,26], including the resting stage (telogen), which lasts for 3-4 months [25].…”

“…In addition, at any given time approximately 15 To of hairs are in the resting stage [20,21]. Therefore, when we attempt to interpret drug exposure history from the information obtained from hair analysis, uncertainty due to these variables should be resolved.…”

Dosage des amphétamines dans les cheveux, la salive et les urines

“…Human hair grows at approximately 1 -1.3 cm per month, and has been measured using various biomarkers (1,2). Hair, due to its growth rate and stability, offers a much longer history of drug exposure than any other matrix.…”