Photostability Studies of Some Analgesic Drugs

Abstract

The present thesis includes a photostability study of oxicam derivative non steroidal antiinflammatory drug (NSAID) lornoxicam (LRX) and tenoxicam (TNX) in dilute aqueous solutions at different pH media. The photodegradation of the mentioned drugs were also studied in the existence of eleven additives (sodium benzoate, p- aminobenzoic acid, tartaric acid, boric acid, citric acid, titanium dioxide, methyl paraben, propyl paraben, caffeine, ascorbic acid and βcyclodextrin). The thesis comprises three chapters:

Chapter I includes an introduction on the importance of photostability studies of drugs, major modes of the photodegradtion of drugs and methods of photostabilization. Also, it includes Introduction and literature survey on the selected photostabilizing agents and the drugs under investigation. Chapter II includes the experimental work, which includes materials, preparation of various solutions, apparatus used and general procedures that were done for photostablity studies of the drugs in their bulk powder, their pharmaceutical formulation and human plasma as well. Chapter III includes the results and discussion. The results showed that: 1- The photodegradation rates of LRX and TNX in diluted aqueous solutions were higher at pH 7 and 10 than at pH 2.