Lidocaine self-sacrificially improves the skin permeation of the acidic and poorly water-soluble drug etodolac via its transformation into an ionic liquid.

Lidocaine self-sacrificially improves the skin permeation of the acidic and poorly water-soluble drug etodolac via its transformation into an ionic liquid. Eur J Pharm Biopharm. 2016 Mar 2; Authors: Miwa Y, Hamamoto H, Ishida T Abstract Poor transdermal penetration of active pharmaceutical ingredients (APIs) impairs both bioavailability and therapeutic benefits and is a major challenge in the development of transdermal drug delivery systems. Here, we transformed a poorly water-soluble drug, etodolac, into an ionic liquid in order to improve its hydrophobicity, hydrophilicity and skin permeability. The ionic liquid was prepared by mixing etodolac with lidocaine (1:1, mol/mol). Both the free drug and the transformed ionic liquid were characterized by differential scanning colorimetry (DSC), infrared spectroscopy (IR), and saturation concentration measurements. In addition, in vitro skin-permeation testing was carried out via an ionic liquid-containing patch (Etoreat patch). The lidocaine and etodolac in ionic liquid form led to a relatively lower melting point than either lidocaine or etodolac alone, and this improved the lipophilicity/hydrophilicity of etodolac. In vitro skin-permeation testing demonstrated that the Etoreat patch significantly increased the skin permeation of etodolac (9.3-fold) compared with an etodolac patch alone, although an Etoreat patch did not increase the skin permeation of lidocaine, which was consistent with...
Source: European Journal of Pharmaceutics and Biopharmaceutics - Category: Drugs & Pharmacology Authors: Tags: Eur J Pharm Biopharm Source Type: research