Gabapentin, 1-(Aminomethyl)cyclohexaneacetic acid, MW 171.240, is a frequently prescribed high dose human medication that is also used recreationally. Gabapentin is orally absorbed; the dose can be 3,000 mg/day and it is excreted essentially unchanged in urine. Gabapentin is stable in the environment and routinely detected in urban wastewater. Gabapentin randomly transfers from humans to racing horses and is at times detected at pharmacologically ineffective / trace level concentrations in equine plasma and urine. In Ohio racing between January 2019 and July 2020,18 Gabapentin identifications, all less than 2 ng/ml in plasma, were reported. These identifications were ongoing because the horsemen involved were unable to pin down and therefore avoid the source of these identifications. Given that 44 ng/ml or less is an Irrelevant Plasma Concentration (IPC) of Gabapentin in horses, we proposed a 5 ng/ml plasma interim Screening Limit of Detection for Gabapentin identifications in Ohio racing, and an essentially similar 8 ng/ml plasma Screening Limit of Detection was suggested by a scientific advisor to the Ohio Horse Racing Commission. As such, an analytical Screening Limit of 8 ng /ml in plasma is an appropriate and pharmacologically conservative analytical “cut-off” or Screening Limit of Detection (SLOD) for Gabapentin in equine competitive events to avoid the calling of “positive” identifications on random unavoidable trace level identifications of this widely prescribed human therapeutic medication in equine forensic samples.

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加巴喷丁，一种人类治疗药物和一种以痕量水平转移给马的环境物质：病例报告

加巴喷丁，1-（氨基甲基）环己烷乙酸，MW 171.240，是一种常用的高剂量人体药物，也可用于娱乐。加巴喷丁口服吸收；剂量可以是 3,000 毫克/天，并且在尿液中排泄基本不变。加巴喷丁在环境中是稳定的，在城市废水中经常检测到。加巴喷丁从人类随机转移到赛马，有时在马血浆和尿液中检测到药理学无效/痕量浓度。在 2019 年 1 月至 2020 年 7 月期间的俄亥俄州比赛中，18 份加巴喷丁鉴定报告在血浆中均低于 2 ng/ml。这些鉴定正在进行中，因为所涉及的骑兵无法确定，因此避免了这些鉴定的来源。鉴于 44 ng/ml 或更低是马中加巴喷丁的不相关血浆浓度 (IPC)，我们提出了 5 ng/ml 血浆临时筛查限，用于俄亥俄州赛马中加巴喷丁鉴定，以及基本相似的 8 ng/ml 血浆俄亥俄赛马委员会的一位科学顾问建议了筛选检测限。因此，血浆中 8 ng/ml 的分析筛选限是加巴喷丁在马竞争事件中的适当且药理学保守的分析“截止”或筛选检测限 (SLOD)，以避免在在马法医样本中对这种广泛使用的人类治疗药物进行随机不可避免的痕量水平鉴定。我们为俄亥俄州赛马中的加巴喷丁鉴定提出了 5 ng/ml 血浆中间筛选检测限，俄亥俄赛马委员会的科学顾问建议了一个基本相似的 8 ng/ml 血浆筛查限。因此，血浆中 8 ng/ml 的分析筛选限是加巴喷丁在马竞争事件中的适当且药理学保守的分析“截止”或筛选检测限 (SLOD)，以避免在在马法医样本中对这种广泛使用的人类治疗药物进行随机不可避免的痕量水平鉴定。我们为俄亥俄州赛马中的加巴喷丁鉴定提出了 5 ng/ml 血浆中间筛选检测限，俄亥俄赛马委员会的科学顾问建议了一个基本相似的 8 ng/ml 血浆筛查限。因此，血浆中 8 ng/ml 的分析筛选限是加巴喷丁在马竞争事件中的适当且药理学保守的分析“截止”或筛选检测限 (SLOD)，以避免在在马法医样本中对这种广泛使用的人类治疗药物进行随机不可避免的痕量水平鉴定。