Stability indicating HPLC method for the estimation of oxycodone and lidocaine in rectal gel

• Published in: International journal of pharmaceutics 2001-07, Vol.223 (1), p.49-54
• Main Authors: Gebauer, Markus G, McClure, Anna F, Vlahakis, Thean L
• Format: Article
• Language: English
• Subjects: Administration, Rectal; Analgesics, Opioid - chemistry; Biological and medical sciences; Chromatography, High Pressure Liquid; Drug Stability; Gels; General pharmacology; HPLC; Lidocaine; Lidocaine - administration & dosage; Lidocaine - analysis; Lidocaine - chemistry; Medical sciences; Oxycodone; Oxycodone - administration & dosage; Oxycodone - analysis; Oxycodone - chemistry; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Rectal gel
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/S0378-5173(01)00729-3

An HPLC method for the quantification of oxycodone and lidocaine in a gel matrix is described. The mobile phase consisted of methanol–water–acetic acid (35:15:1 v/v/v) and was delivered at 1.5 ml/min through a 4.6×250 mm Zorbax® SB-C8 column. Oxycodone was detected at 285 nm and lidocaine at 264 nm. Linear calibration curves were obtained for oxycodone in the range of 0.05–1.5% (w/w) and for lidocaine in the range of 0.1–5.0% (w/w). Oxycodone and lidocaine were treated with hydrogen peroxide and the oxidation products were readily separated on the column. The method was applied to assess the stability of a gel containing oxycodone hydrochloride (0.3% w/w) and lidocaine (1.5% w/w). The gel was stored under refrigeration in ready-to-use syringes and under these conditions oxycodone and lidocaine were stable for at least 1 year. The gel is useful in the management of tenesmus in rectal cancer.