This study concern a survey of bacterial resistance to cotrimoxazole; 510 strains of Enterobacteria (167), Vibrio cholerae(206) and Staphylococcus aureus(137) were tested by disc diffusion and agar dilution methods. An interview was conducted with 86 health personals to appreciate the influence of prescription. Staphylococcus aureus were the most susceptible bacteria (13% of resistance), and Vibrio cholerae the most resistant (95%). Related to the gender, Enterobacteria present 43 to 72% of resistance. The data of interview show a very frequent use of cotrimoxazole, related to the disponibility and the accessibility of this drug.