Promazine is one of the oldest phenothiazine derivatives that have been proposed for the treatment of various psychiatric disorders. The drug is available as tablets, as syrups and in injectable forms. Despite its prescription to millions of subjects, its detection in human hair has seldom been reported. The aim of the present work is to develop a specific method to identify promazine in human hair by liquid chromatography–tandem mass spectrometry and to apply it to a patient who was self-medicating. The method involves overnight incubation of 20 mg of cut hair in 1 mL of pH 9.5 borate buffer in the presence of amitriptyline-d3 at 40°C. The chromatographic separation was performed using a reverse phase column HSS C18 with a gradient elution for 15 min. Linearity was verified from 0.5 to 500 pg/mg (r2 = 0.9996), after spiking blank hair with the corresponding amounts of promazine. The limit of detection was estimated at 0.1 pg/mg. The precision was lower than 20%. Promazine was detected in the hair of a psychotic subject at 228–270 pg/mg in a 3 × 1 cm segment. Given this was a patient who was self-medicating, her physician requested an immediate drug discontinuation. In a fresh hair specimen collected 3 months later, the proximal segment (0–1 cm) tested positive at 0.9 pg/mg, clearly indicating that the time to obtain a negative result after promazine discontinuation is about 3–4 months.

中文翻译：

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人类头发中的丙嗪检测：介绍一种 LC-MS/MS 方法和药物停药模式

Promazine 是最古老的吩噻嗪衍生物之一，已被提议用于治疗各种精神疾病。该药物有片剂、糖浆和注射剂形式。尽管它对数百万受试者的处方，它在人类头发中的检测很少被报道。本工作的目的是开发一种通过液相色谱-串联质谱法鉴定人发中丙嗪的特定方法，并将其应用于自我治疗的患者。该方法包括在 40°C 下，在阿米替林-d3 存在下，将 20 mg 剪发的头发在 1 mL 的 pH 9.5 硼酸盐缓冲液中孵育过夜。使用反相色谱柱 HSS C18 进行色谱分离，梯度洗脱 15 分钟。在 0.5 至 500 pg/mg (r2 = 0.9996) 范围内验证了线性，在用相应量的丙嗪掺入空白头发后。检测限估计为 0.1 pg/mg。精度低于 20%。在 3 × 1 cm 段的精神病受试者的头发中检测到丙嗪，浓度为 228–270 pg/mg。鉴于这是一名自行服药的患者，她的医生要求立即停药。在 3 个月后采集的新鲜头发样本中，近端（0-1 cm）检测为阳性，浓度为 0.9 pg/mg，清楚地表明停用丙嗪后获得阴性结果的时间约为 3-4 个月。她的医生要求立即停药。在 3 个月后采集的新鲜头发样本中，近端（0-1 cm）检测为阳性，浓度为 0.9 pg/mg，清楚地表明停用丙嗪后获得阴性结果的时间约为 3-4 个月。她的医生要求立即停药。在 3 个月后采集的新鲜头发样本中，近端（0-1 cm）检测为阳性，浓度为 0.9 pg/mg，清楚地表明停用丙嗪后获得阴性结果的时间约为 3-4 个月。