The retrospective calendar of an individual's drug use requires a multisectional analysis in which the length of hair, corresponding to the full temporal window available, is cut into shorter sections to measure drug use during shorter periods of time (generally 1 cm corresponds to ~1 month). Segmental hair analysis is used to verify both previous drug history and recent enforced abstinence. However, after drug discontinuation, the fresh new hair growth segment cannot be immediately negative, due to the contribution of dormant hair. The objective of the study was to test hair samples from chronic tramadol and cannabis users after the discontinuation of both drugs and to evaluate the delay to wait until the hair will become negative. Hair specimens were obtained from eight subjects with a known history of tramadol abuse. Hair was collected 3-6 months after tramadol discontinuation. Tramadol was tested by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with a LOQ at 5 pg/mg. A second set of hair specimens were obtained from 15 subjects with a known history of cannabis abuse. Hair was collected 6-9 months after cannabis discontinuation. THC-COOH was tested by LC-MS-MS with a LOQ at 0.2 pg/mg. The hair stands were cut into L × 1 cm segments, according to their length (L), and tested for the respective drug. It was asked to each subject to clearly indicate the date of drug discontinuation. Assuming a rate of hair growth of 1 cm/month, the segment corresponding to the time of last drug use was calculated. The older segment just before this one was considered as the 100% of the response. THC-COOH and tramadol concentrations in this segment ranged from 2.3 to 8.9 and 895 to 21,010 pg/mg, respectively. After cessation of drug consumption, the presence of both drugs in new growing hair segments continued for a certain period with a more or less broad transition zone. Negative hair results were obtained ~3-4 and 6-7 months after cessation of tramadol and cannabis abuse.

中文翻译：

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滥用终止后，曲马多和THC-COOH在头发中消失。两种不同的配置文件。

回顾个人药物使用情况的日历需要进行多部分分析，其中将与可用的整个时间窗相对应的头发长度切成较短的部分，以测量较短时间段内的药物使用情况（通常1厘米对应于大约1个月） ）。分段毛发分析用于验证既往的药物史和最近的强制戒断。但是，停药后，由于休眠的头发的影响，新鲜的新头发生长部分不能立即变为阴性。该研究的目的是在两种药物停用后测试来自长期曲马多和大麻使用者的头发样品，并评估等待直到头发变阴性的延迟时间。头发标本来自八名已知有曲马多滥用史的受试者。曲马多停用后3-6个月收集头发。曲马多通过液相色谱-串联质谱（LC-MS-MS）进行测试，LOQ为5 pg / mg。从已知大麻滥用史的15名受试者中获得第二组头发样本。大麻停用后6-9个月收集头发。THC-COOH通过LC-MS-MS进行测试，LOQ为0.2 pg / mg。根据其长度（L）将发架切成L×1 cm的小段，并测试相应的药物。要求每个受试者清楚地指示停药的日期。假设毛发生长率为1厘米/月，则计算出与上次使用药物时间对应的时间段。在此之前的较旧部分被认为是响应的100％。在此部分中，THC-COOH和曲马多的浓度分别为2.3至8.9 pg / mg和895至21,010 pg / mg。停止吸毒后，两种药物在新生长的发丝段中的存在持续了一段时间，过渡区域或多或少。曲马多和大麻滥用停止后约3-4和6-7个月获得了阴性的头发结果。