Oral fluid cocaine and benzoylecgonine concentrations following controlled intravenous cocaine administration

Abstract

Limited oral fluid (OF) pharmacokinetic data collected with commercially available collection devices after controlled cocaine administration hinder OF result interpretations. Ten cocaine-using adults provided OF, collected with Oral-Eze® (OE) and StatSure Saliva Sampler™ (SS) devices, an hour prior to and up to 69 h after 25 mg intravenous (IV) cocaine administration. Cocaine and benzoylecgonine (BE) were quantified by a validated 2D-GC-MS method. Large inter-subject variability was observed. Cocaine was detected in OF in the first 0.17 h sample after IV administration, with much more rapid elimination than BE. OE median observed Cmax (range) was 932 (394–1,574) μg/L for cocaine and 248 (96.9–953) μg/L for BE. SS median (range) observed cocaine and BE Cmax trended lower at 732 (83.3–1,892) μg/L and 360 (77.2–836) μg/L, respectively. OE and SS cocaine OF detection times were 12.5 and 6.5 h and for BE 30.5 and 28.0 h, respectively at 1 μg/L. There were no significant pharmacokinetic differences between OE and SS OF collection devices, except cocaine half-life was significantly shorter in SS OF specimens. This difference could be attributed to differences in stabilizing buffers present in OF collection devices, which may affect cocaine stability in OF specimens, or decreased recovery from collection pads. Both OE and SS OF collection devices were effective in monitoring cocaine and metabolite concentrations with similar detection windows. Furthermore, we demonstrated that different confirmatory OF cutoffs can be selected to produce shorter or longer cocaine and metabolite detection windows to address specific needs of clinical and forensic drug testing programs.

A Study on the Reliability of an On-Site Oral Fluid Drug Test in a Recreational Context

“…In this concern, previous studies demonstrated that cocaine was predominantly found in oral fluid with respect to its principal metabolite benzoylecgonine, present in very low concentrations in this biological matrix [ 3 , 9 ]. Furthermore, recently, it has been demonstrated that oral fluid concentration of benzoylecgonine and the relationship with cocaine are time dependent, unless cocaine is intravenously administered [ 32 ]. Since benzoylecgonine extraction by HS-SPME and detection would have presented a great analytical difficulty due to its polar nature, this metabolite was not considered in this study.…”

Positivity to Cocaine and/or Benzoylecgonine in Confirmation Analyses for On-Road Tests in Spain

“…The pharmacokinetics of cocaine has been studied in various ways [ 12 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ]. In controlled administration studies, cocaine was identified in OF after smoking, intravenous, intranasal and oral administration [ 8 , 24 , 25 ].…”

“…Cocaine is largely metabolized into the body, with benzoylecgonine (BZE) being the major inactive metabolite [ 11 , 12 ]. Current OF roadside drug testing and laboratory confirmation analyses detect cocaine and their main inactive metabolite BZE.…”

Cocaine and benzoylecgonine oral fluid on‐site screening and confirmation

“…A 'Positive/Negative' or 'Invalid' (if improper lateral flow was detected) response occurs following lateral flow immunochromatography. Cocaine and/or BE confirmation was performed by a fully validated 2D-GC-MS method, [28] in accordance with the Scientific Working Group for Forensic Toxicology recommendations. [29] Linear ranges were 1-100 μg/L.…”