Pharmaceuticals production and their consumption by the world population have increased in recent years; as a result, these contaminants have reached the water. In this study, the presence and concentration of the anti-inflammatory drug piroxicarn and the anti-hypertensive and beta-blocker atenolol were evaluated in la Onca stream, Tres Lagoas, MS, Brazil, and the influence of water temperature in the occurrence of these drugs in surface waters was verified. Monitoring of both drugs and water temperature was carried out in the