Department of Neurology, The Second People's Hospital of Yunnan Province, Yunnan, China.
Innoscience Research Sdn Bhd, Selangor, Malaysia.
Drug Dev Ind Pharm. 2020 Feb;46(2):264-271. doi: 10.1080/03639045.2020.1716377. Epub 2020 Jan 30.
Topical drug delivery for local anesthetics has been an interesting area of research for formulators considering the resistance and barrier properties of skin and high clearance rate of drugs like prilocaine and lidocaine (duration of action < 2.5 h). In this study, efforts have been made to sustain the release of prilocaine and lidocaine by using depot microemulsion system. Drug loaded microemulsions were formulated using Capmul MCM, Pluronic F127, polyethylene glycol 200 (PEG 200) and water from pseudo-ternary diagrams. The S at 1:4 ratio showed larger microemulsion area in comparison to 1:2 ratio. The studies indicate sustained release of prilocaine and lidocaine from the microemulsion up to 8 h, in comparison to 4 h with ointments. Skin irritation study on rabbits confirmed the safety of drug loaded microemulsions for local drug delivery. The improved data is reflected in the studies, were radiant heat tail-flick test and sciatic nerve model showed prolong duration of action for both prilocaine and lidocaine microemulsions in comparison to ointment. The and efficacy of prilocaine and lidocaine was non-significant. The improved efficacy was due to high penetration of microemulsion and depot effect due to local precipitation (destabilization of microemulsion) of drug in the skin layer. The sustained local anesthetic effect is highly desirable for the treatment of skin irritation due to skin burns and pre- and post-operative pain.
局部麻醉剂的经皮给药一直是制剂学家感兴趣的研究领域，因为皮肤具有抗药性和屏障特性，而且普鲁卡因和利多卡因等药物的清除率很高（作用持续时间<2.5 小时）。在这项研究中，我们努力通过使用储库型微乳系统来维持普鲁卡因和利多卡因的释放。采用伪三元相图，用 Capmul MCM、Pluronic F127、聚乙二醇 200（PEG 200）和水制备载药微乳。S 为 1:4 比例时，与 1:2 比例相比，显示出更大的微乳区域。研究表明，与软膏相比，微乳中普鲁卡因和利多卡因的释放可延长至 8 小时，而软膏中仅为 4 小时。兔皮肤刺激性研究证实了载药微乳用于局部给药的安全性。改进的数据反映在研究中，辐射热尾部闪烁试验和坐骨神经模型表明，与软膏相比，普鲁卡因和利多卡因微乳的作用持续时间更长。普鲁卡因和利多卡因的 和 疗效无显著差异。疗效的提高是由于微乳的高渗透性和由于药物在皮肤层中的局部沉淀（微乳的失稳）而产生的储库效应。由于皮肤烧伤和手术前后疼痛引起的皮肤刺激，持续的局部麻醉效果是非常理想的。
