Résumé
Sulfonamides are the drug of choice for number of infections like pneumonia, toxoplasmosis, nocardiosis, urinary tract infections. Sulfonamides are most commonly used in combinations such as [Trimethoprim-Sulfamethoxazole] [TMP+SMZ] or co-trimoxazole. Sixty five isolates belonging to five different species, E. coli [22], S. aureus [18], Klebsiella [05], Pseudomonas [16] and Proteus [04] were used for screening antibacterial activity against different brands [A-G] of Co-trimoxazole by disc diffusion method. Brand G exhibited highest activity against E. coli with mean zone of inhibition 41mm +/-2.3 standard deviation. The antibacterial activity against other species S. aureus, Klebsiella and Pseudomonas were found as: [mean +/- standard deviation] observed as 39.73 mm +/- 10.59 mm +/- 38 mm +/- 2 and 24.93 mm +/- 5.32. However all isolates of Proteus were found resistant against different brands of co-trimoxazole