Sawynok Jana, Zinger Celia
a Department of Pharmacology , Dalhousie University , Halifax , Canada.
b VeraMed Consulting, Ltd , Mahe , Seychelles.
Expert Opin Pharmacother. 2016;17(4):601-9. doi: 10.1517/14656566.2016.1146691.
Neuropathic pain (NP) has several therapeutic options but efficacy is limited and adverse effects occur, such that additional treatment options are needed. A topical formulation containing amitriptyline 4% and ketamine 2% (AmiKet) may provide such an option.
This report summarizes both published and unpublished results of clinical trials with AmiKet. In post-herpetic neuralgia (PHN), AmiKet produces a significant analgesia which is comparable to that produced by oral gabapentin. In diabetic painful neuropathy, AmiKet showed a strong trend towards pain reduction. In mixed neuropathic pain, case series reports suggest a favourable response rate, but are limited by trial characteristics. AmiKet is absorbed minimally following topical administration. Over 700 patients have now received topical AmiKet in clinical regimens, and it is well-tolerated with the adverse effects mainly being application site reactions. Both agents are polymodal, and several mechanisms may contribute to the peripheral efficacy of AmiKet.
Topical AmiKet has the potential to be a first-line treatment option for PHN, and to be useful in other NP conditions. Furthermore, AmiKet has the potential to be an adjunct to systemic therapies, with the targeting of a peripheral compartment in addition to central sites of action representing a rational drug combination.
神经性疼痛（NP）有多种治疗选择，但疗效有限且会出现不良反应，因此需要更多的治疗选择。一种含有4%阿米替林和2%氯胺酮的外用制剂（AmiKet）可能提供这样一种选择。
本报告总结了AmiKet临床试验的已发表和未发表结果。在带状疱疹后神经痛（PHN）中，AmiKet产生显著的镇痛效果，与口服加巴喷丁产生的效果相当。在糖尿病性疼痛性神经病变中，AmiKet显示出明显的疼痛减轻趋势。在混合性神经性疼痛中，病例系列报告显示有效率良好，但受试验特点限制。外用AmiKet后吸收极少。目前已有700多名患者在临床治疗中接受了外用AmiKet，耐受性良好，不良反应主要为用药部位反应。两种药物均具有多模式作用，几种机制可能有助于AmiKet的外周疗效。
外用AmiKet有潜力成为PHN的一线治疗选择，并对其他NP病症有用。此外，AmiKet有潜力成为全身治疗的辅助药物，除了作用于中枢部位外，靶向外周部位代表一种合理的药物组合。
