乙醇对丁卡因凝胶透皮和局麻作用的影响

目的 :考察透皮吸收促进剂乙醇对丁卡因凝胶透皮和局麻作用的影响。方法 :以卡波姆 940为基质配制含 2 0 %和 70 %乙醇的丁卡因 (4 % ,w w)凝胶。采用Franz扩散小池和紫外分光光度法进行小鼠离体皮肤渗透试验 ;用VonFrey镇痛试验考察丁卡因凝胶的局麻作用。结果 :离体皮肤渗透试验表明 2 0 %和 70 %乙醇对丁卡因凝胶均有较强的促渗作用 (P <0 .0 5 ) ,其渗透速率K分别提高了 1 .5 3倍和 2 .1 2倍 ,其中 70 %乙醇的促渗作用明显强于2 0 %乙醇 (P <0 .0 1 ) ,但是 70 %乙醇在一定程度上延长了丁卡因凝胶的滞后时间 ;VonFrey镇痛试验显示含 70 %乙醇的丁卡因凝胶局麻镇痛作用于用药后 1h达高峰 ,痛觉抑制百分率为 1 1 3 % ,镇痛作用持续 5h。结论 :含 70 %乙醇的丁卡因凝胶剂具有较强的透皮作用和局麻效果

Enhancement of ethanol on percutaneous permeation and topical anaesthesia of tetracaine gel

AIM: To investigate the enhancement of ethanol on percutaneous permeation and topical anaesthesia of tetracaine gel. METHODS: Tetracaine (4%, w/w) gels were prepared by using 20% and 70% ethanol as penetration enhancers. Franz diffusion chamber and UV spectrophotometry were adopted in the transdermal osmotic test of isolated mouse skin. Von Frey test was used to evaluate the topical anesthetic effect of tetracaine gels. RESULTS: 20% and 70% ethanol greatly improved the percutaneous permeation of tetracaine gel (P< 0.05 ). Penetration rates were 1.53 - 2.12 times over that of tetracaine gel without penetration enhancer. Statistical analysis indicated that tetracaine gel with 70% ethanol was better than that with 20% ethanol (P< 0.01 ), however, the lag time prolonged. Von Frey test demonstrated that the maximum pain restrain percentage of tetracaine gel with 70% ethanol reached 113% after its one hour topical use and the duration anaesthesia was five hours. CONCLUSION: Tetracaine gel containing 70% ethanol may become a new formulation with ideal percutaneous permeation and topical anesthetic effect.