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This study investigated the disposition patterns of cocaine and opiates into hair and fingernail specimens collected from 8 volunteers enrolled in a 10-week inpatient clinical study. All subjects were African-American males with a confirmed drug use history. Scalp hair and fingernail scrapings were collected weekly throughout the course of the study. Head hair was collected from the posterior vertex region, and fingernail scrapings were collected along the entire ventral surface of the nail plate. The specimens were introduced to successive decontamination washes including an isopropanol wash and three phosphate buffer washes. All decontamination washes were collected and analyzed. All specimens were enzymatically digested prior to being subjected to solid-phase extraction and derivatization. Analyses were performed using electron impact gas chromatography-mass spectrometry. Analytes investigated included eight cocaine analytes and five codeine analytes. The limit of quantitation for all analytes ranged from 0.1 to 0.5 ng/mg for both matrices. Cocaine was present at the highest concentrations of any analyte in both hair and nail. Benzoylecgonine and ecgonine methyl ester were the primary metabolites in both matrices and were typically less than 15% of cocaine concentrations. Codeine was the only opiate analyte identified in either hair or nail. Observed drug disposition profiles were different for hair and nails. A significant dose-response relationship was observed for hair specimens. The mean peak concentrations in hair after low dosing were half the concentration observed after high-dose administration. Generally, no clear relationship was evident between nail drug concentrations and dose. Decontamination washes removed less than 20% of the total drug present in hair, but removed most of the drug concentrations (60-100%) in nail. This investigation demonstrated that higher concentrations of drug were found in the subjects' hair than in their fingernails and that cocaine was found in both matrices at a greater concentration than codeine. Although both hair and nail have similar physical and chemical properties and may share common mechanisms of drug incorporation, this clinical study suggests that there are distinct differences in their disposition profiles.

Background: Confirmation of a workplace drug test requires urinary methamphetamine (MAMP) and amphetamine (AMP) concentrations ≥500 and 200 μg/L, respectively, but cutoffs at half those values (250/100 μg/L) have been proposed. We determined the urinary excretion of MAMP after oral ingestion and examined the effect of using lower cutoffs on detection of exposure. Methods: Volunteers (n = 8) ingested four 10-mg doses of MAMP · HCl daily over 7 days, and five of them ingested four 20-mg doses 4 weeks later. After ingestion, the volunteers collected all urine specimens for 2 weeks. After solid-phase extraction, MAMP and AMP were measured by gas chromatography–positive chemical ionization mass spectrometry with dual silyl derivatization. Results: MAMP and AMP were generally detected in the first or second void (0.7–11.3 h) collected after drug administration, with concentrations of 82–1827 and 12–180 μg/L, respectively. Peak MAMP concentrations (1871–6004 μg/L) after single doses occurred within 1.5–60 h. MAMP ≥500 μg/L was first detected in the first or second void (1–11 h) at 524-1871 μg/L. Lowering the MAMP cutoff to 250 μg/L changed the initial detection time little. AMP ≥200 μg/L was first detected in the 2nd–13th (7–20 h) post-administration voids. At a cutoff of 100 μg/L, AMP was first confirmed in the second to eighth void (4–13 h). Reducing the cutoff to 250/100 μg/L extended terminal MAMP detection by up to 24 h, increased total detection time by up to 34 h, and increased the total number of positive specimens by 48%. Conclusions: At the lower cutoff, initial detection times are earlier, detection windows are longer, and confirmation rates are increased. Elimination of the AMP requirement would increase detection rates and allow earlier detection.

Background: The ease, noninvasiveness, and safety of oral fluid collection have increased the use of this alternative matrix for drugs-of-abuse testing; however, few controlled drug administration data are available to aid in the interpretation of oral fluid results. Methods: Single oral codeine doses (60 and 120 mg/70 kg) were administered to 19 volunteers. Oral fluid and plasma were analyzed for free codeine, norcodeine, morphine, and normorphine by solid-phase extraction combined with gas chromatography–mass spectrometry (SPE/GC-MS). Physiologic and subjective effects were examined. Results: Mean (SE) peak codeine concentrations were 214.2 ± 27.6 and 474.3 ± 77.0 μg/L in plasma and 638.4 ± 64.4 and 1599.3 ± 241.0 μg/L in oral fluid. The oral fluid-to-plasma ratio for codeine was relatively constant (∼4) from 1 to 12 h. The mean half-life (t1/2) of codeine was 2.2 ± 0.10 h in plasma and 2.2 ± 0.16 h in oral fluid. Significant dose-related miosis and increases in sedation, psychotomimetic effect, and “high” occurred after the high dose. Mean codeine oral fluid detection time was 21 h with a 2.5 μg/L cutoff, longer than that of plasma (12–16 h). Detection times with the proposed Substance Abuse and Mental Health Services Administration cutoff (40 μg/L) were only 7 h. Norcodeine, but not morphine or normorphine, was quantified in both plasma and oral fluid. Conclusions: The disposition of codeine over time was similar in plasma and oral fluid, but because of high variability, oral fluid codeine concentrations did not reliably predict concurrent plasma concentrations. Oral fluid testing is a useful alternative matrix for monitoring codeine exposure with a detection window of 7–21 h for single doses, depending on cutoff concentrations. These controlled drug administration data should aid in the interpretation of oral fluid codeine results.