Extemporaneously Compounded Topical Calcium Channel Blockers for Wounds and Skin Ulcers

Abstract

Compounded topical calcium channel blockers are used for the treatment of wounds, such as anal fissures and diabetic ulcers. Diltiazem and nifedipine are the calcium channel blockers with the most evidence for topical use. They are compounded extemporaneously with cream, gel, and ointment bases. However, drug release and stability information on these formulations is scarce. This project aimed to: (1) establish drug release profiles of compounded topical nifedipine and diltiazem in commonly used cream, gel and ointment bases using Franz diffusion cell system, and (2) determine shelf-life and beyond-use dates of products stored in white plastic and glass amber containers at room (23°C), refrigerator (4°C) and elevated (40°C) temperatures for 90 days. The cream and gel had the highest release and optimal stability for nifedipine and diltiazem, respectively. This study provides pharmacists with the scientific rationale for compounding bases selection and storage of topically compounded nifedipine and diltiazem products.