Aim: This study was undertaken to determine the antimicrobial and antifungal effect of BioPure MTAD, Metapex and aztreonam against Enterococcus faecalis and Candida albicans. Materials and method: The testing of the antimicrobial and antifungal efficacy of selected medicaments against Enterococcus faecalis and Candida albicans was done by the agar disc-diffusion method. Pre-sterilised Whatman paper discs, 6 mm in diameter and soaked with the test solution, were prepared and placed onto the previously seeded agar petri plates. Each plate was incubated at 37°C for 48 hours. A zone of inhibition was recorded for each plate and the results were analysed statistically. Saline and ethanol were used as control groups in this study. Results: BioPure MTAD was effective against all the test microorganisms with a substantial zone of inhibition. Saline and ethanol used as controls were ineffective. Metapex and aztreonam showed a significantly larger average zone of inhibition against E. faecalis, but were not effective against C. albicans. Conclusions: BioPure MTAD was found to be superior in its antimicrobial and antifungal abilities compared with the other irrigants used. When Metapex and aztreonam were compared, Metapex showed a greater antimicrobial effect, but both failed to show any antifungal effect. Keywords: aztreonam, Biopure MTAD, C. albicans, E. faecalis, Metapex