Evaluation of antibacterial effects of chlorzoxazone

Purpose: Some of non-antibiotic drugs may provide inhibition against bacterial growth in their routine use. Chlorzoxazone is a muscle relaxant used to treat muscle spasm and the resulting pain or discomfort. This study was aimed to the investigation of antibacterial effects of Chlorzoxazone using MIC (Minimum inhibitory concentration), MBC (minimum bactericidal concentration) and disk diffusion method. Materials and Methods: The MIC and MBC was determined by dilution assay using different concentrations of Chlorzoxazone against 2 bacterial strain (Pseudomonas aeruginosa as a gram negative bacterial strain and Bacillus subtilis as a gram positive bacterial strain). Disk diffusion assay were prepared at different doses (25, 50 and 100 μg). Results: MIC values of Chlorzoxazone against Pseudomonas aeruginosa was 0.800 mg ml-1, and MBC values was 2.56 mg ml-1 and MIC values of Chlorzoxazone against Bacillus subtilis was 0.400 mg ml-1, and MBC values was 1.92 mg ml-1. The results obtained from disk diffusion assay supported that the Chlorzoxazone has not antibacterial effect on Pseudomonas aeruginosa and Bacillus subtilis. Conclusion: Although antibacterial activity of Chlorzoxazone was not found but another studies are needed to determine the probable risk of Chlorzoxazone