In this paper we have studied the photodegradation of omeprazole in aqueous solution, this medicament is the active ingredient in many antacids widely used worldwide. Omeprazole used in the experiments of degradation was obtained by the process of solid-liquid extraction from a generic brand commercial medicament. The degradation experiments were carried out in a reactor illuminated with low energy UV light lamps using TiO₂ Degussa P25 as catalyst. The experimental results indicate that the organic compound is easily degraded in a very short period of time. However, the omeprazole molecule is not mineralized in a rapid manner. In the same way as other aromatic compounds, omeprazole is transformed to other organic compounds before being mineralized to CO₂ and water.