Study of Photostability of Finasteride, Diclofenac, and Naproxen Through Exposure to Simulated Sunlight and Evaluation of Packaging Photoprotection of These Drugs

The study evaluated the photostability of Finasteride, Diclofenac, and Naproxen under simulated sunlight conditions to assess how light exposure affected these drugs. Using a special lamp to mimic natural sunlight, the drugs were tested both as active ingredients in solvents and in solid dosage forms. High-performance liquid chromatography (HPLC) was used to monitor the concentration of the substances. After 90 hours of exposure at 600 W/m², Finasteride retained 57% of its concentration, while Diclofenac and Naproxen retained only 12% and 9%, respectively, indicating that Finasteride was more photostable compared to the other two drugs.