ABSTRACT: Background: The quality of medicines available in some developing countries is inadequate in terms of content of active ingredients. A previous study with metronidazole tablets from different pharmaceutical industries in Bangladesh has shown these as good as standard metronidazole against clinical isolates of Entamoeba histolytica. Other anti-amoebic drugs, such as secnidazole and tinidazole tablets, obtained from different pharmaceutical companies in Bangladesh may also be effective against clinical isolates of E. histolytica. Objective: Evaluate in-vitro sensitivity of different brands of secnidazole and tinidazole tablets from different pharmaceutical companies of Bangladesh against clinical isolates of E. histolytica. Methodology: An in-vitro drug sensitivity study was carried out with randomly-selected 3 different brands of secnidazole tablets and one brand of tinidazole tablet collected from different retail medicine shops in Bangladesh. Different concentrations of the standard and the sample secnidazole and tinidazole were prepared. Clinical isolates of E. histolytica were harvested from 24 hours old cultures and suspended in an axenic medium (LYI-S-2). The parasite count was adjusted to 3×106 parasites/mL in a medium. The samples were assayed by using microtitre plates after treatment with different concentrations of drugs. The viable parasites were counted by haemocytometer. Descriptive statistical analyses were done by one-way ANOVA using the SPSS software (version 12.0); a probability level of 0.05 was considered statistically significant. Results: The mean viable parasites after treatment with 3 secnidazole samples at the concentration of 4.32µM were 6±1.00; 7±0.58, and 11±2.08, and none of the differences was significant when compared with standard. Tinidazole tablet inhibited about 89% of E. histolytica at the concentrations of 3.2 µM. Conclusion: The study concludes that all brands of secnidazole tablets inhibit above 80% of E. histolytica at different concentrations. However, tinidazole can inhibit about 89% of E. histolytica only at higher concentrations. The findings may help raise awareness among physicians to select quality products. Acknowledgements: The authors acknowledge the authority of Parasitology Laboratory, Laboratory Sciences Division, ICDDR,B, for providing support to carry out the study.
12th Annual Scientific Conference(ASCON XII)., ICDDR,B, Dhaka, Bangladesh.; 01/2009