Dextromethorphan (DXM) is a safe and effective antitussive agent present in several over the counter cough and cold medications. At higher doses, it causes psychoactive effects, making it appealing for abuse. In this work, the pharmacokinetics and pharmacodynamics of DXM with clinical and forensic relevance were extensively reviewed. DXM and related known metabolizing enzymes and metabolites were searched in books and in PubMed (U.S. National Library of Medicine) without a limiting period. Major metabolic pathways include sequential O-demethylation and N-demethylation of DXM, yielding dextrorphan (DXO), the major active metabolite, and 3-hydroxymorphinan, the bi-demethylated product, respectively. The demethylation order described may reverse being the resultant mid product 3-methoxymorphinan. UDP-glucuronosyltranferase produces glucuronide conjugates. Genotypic variations in enzymes and interactions with other drugs can result in large inter-individual variability in the pharmacological and toxicological effects produced. Knowing the metabolism of DXM may help to better understand the inter-individual variability in the pharmacokinetics and pharmacodynamics and to avoid adverse effects.

中文翻译：

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右美沙芬的药代动力学和药效学：临床和法医方面。

右美沙芬（DXM）是一种安全有效的镇咳药，存在于多种非处方止咳药和感冒药中。在较高剂量下，它会引起精神上的影响，使其对滥用具有吸引力。在这项工作中，对具有临床和法医相关性的DXM的药代动力学和药效学进行了广泛的综述。在书本和PubMed（美国国家医学图书馆）中没有限制期限地搜索DXM和相关的已知代谢酶和代谢物。主要的代谢途径包括依次进行DXM的O-去甲基化和N-去甲基化，分别产生主要活性代谢物右美沙芬（DXO）和双去甲基化产物3-hydroxymorphinan。所描述的脱甲基顺序可以相反是所得的中间产物3-甲氧基吗啡喃。UDP-葡萄糖醛酸糖基转移酶产生葡糖醛酸苷缀合物。酶的基因型变异以及与其他药物的相互作用可能导致所产生的药理和毒理学效应在个体间产生很大的差异。了解DXM的代谢可能有助于更好地了解药代动力学和药效学之间的个体差异，并避免产生不良影响。