Stability of Methimazole in Poloxamer Lecithin Organogel to Determine Beyond-Use Date
Author(s): Pignato Alyssa, Pankaskie Marvin, Birnie Christine
Issue: Nov/Dec 2010 - Volume 14, Number 6
View All Articles in Issue
Abstract: The purpose of this stability study was to determine the beyond-use date of the active ingredient methimazole extemporaneously prepared for transdermal absorption to treat feline hyperthyroidism. The methimazole was prepared in poloxamer lecithin organogel and subjected to a three-month stability study. It was determined that under room temperature conditions (25°C ± 2°/60% RH ± 5%) the methimazole concentration remained above 90% after 62 days. An accelerated condition of 35°C and refrigerated condition of 5°C were also employed to see how temperature affected the stability of the drug. Under all three conditions the methimazole concentration dropped below 90% after day 62. It was observed that the refrigerated conditions appeared to be least stable both physically and chemically. A control sample was also prepared, stored, and packaged similarly to the sample preparations. As a result, the beyond-use date was determined to be 60 days at room temperature. The drug preparation should not be stored in a refrigerated condition.
Related Keywords: Alyssa Pignato, BS, Marvin Pankaskie, PhD, Christine Birnie, RPh, PhD, methimazole, topical preparation, transdermal administration, feline, cat, hyperthyroidism, stability, storage conditions, temperature, formulation
Related Categories: FORMULATIONS, PEER-REVIEWED, STABILITIES, COMPATIBILITIES, VETERINARY, DOSAGE FORMS/DRUG CARRIERS, STORAGE