Testing the cytotoxicity and genotoxicity of the antimalarial drug mefloquine

Numerous drugs show significant behavioral, developmental, teratogenic and mutagenic effects. This study investigates the cytotoxic and genotoxic effects of two doses (20 and 40 mg/kg body weight) of the antimalarial drug mefloquine (MQ), in male mice. The parameters included the assessment of: mitotic index, cell cycle kinetics, and frequency of chromosomal aberrations in bone marrow cells, translocation frequency in spermatocytes and head and tail abnormalities in sperm. A high dose of mefloquine resulted in a decreased mitotic index, suggesting a dose– response correlation. A notable recovery in mitotic activity was observed during the first and third week post treatment, which approached the mitotic index of control. Chromosomal abnormalities including gaps, breaks, and fragments also increased with the higher dose of mefloquine. Spermatids and secondary spermatocytes were moderately sensitive to the drug; whereas primary spermatocytes were more sensitive, and spermatogonia were highly sensitive to both doses of MQ. Conclusion: Mefloquine (MQ) at the doses used can be considered as a drug with a potential mutagenic effect. The results obtained from the spermatocyte diakinesis-metaphase 1 test and sperm abnormalities suggest that MQ may contribute to high incidence of birth defects and congenital abnormalities.