EXTERNAL MEDICINE COMPOSITION

PURPOSE:To obtain a medicinal composition for external use, which contains a diclofenac or a gel base, thus has spreadability and expandability and shows good skin permeation and percutaneous absorption with excellent application feeling. CONSTITUTION:Diclofenac or its salts are dissolved in a lower alcohol such as isopropanol and the solution is combined with an aqueous solution of a gelling agent such as a carboxyvinyl polymer, a common solvent such as propylene glycol, and further other ingredients. Then, a neutralizing agent such as diethyl-amine is added to adjust the pH to 5.5-8. When needed, menthol can be formulated as a percutaneous absorption accelerator. A neutralizing agent to be used for gelling is selected to increase the percutaneous absorption of diclofenac and the addition of menthol further improves the absorption.