Ivermectin (IVM) is widely used in human and veterinary medicine for the control of parasitic infections. Researches revealed new avenues of medicinal applications of IVM as an antiviral and an anticancer agent. Very little is known about the genotoxic potential of IVM and the available literature is contradictory. The objective of this study was to evaluate the possible genetic damage caused by IVM. Male Sprague Dawley rats were intraperitoneally given IVM at doses between 0.2 mg and 3.2 mg/kg body weight (b. w). Percentages of mitotic and aberrant bone marrow cells were followed. The results indicated that IVM by itself, at doses higher than the recommended dose, induced significant levels of cytogenetic toxicity. To this end, we decided to investigate the potential use of combination of varying doses of aged garlic extract (AGE); 300, 600 and 1200 mg/kg b w and the minimum detectable toxic (MDT) dose of IVM; 0.4 mg/kg. A powerful capacity of AGE to reduce IVM cytogenetic effects was demonstrated. Overall, the data prove the safety of IVM at the recommended dose and provide a strong scientific evidence for superior protection of AGE against possible cytogenotoxic side effects of IVM, confirming the existence of a meaningful therapeutic window. Display omitted •Ivermectin is a broad spectrum antiparasitic drug.•Cytogenetic data on IVM use are contradictory.•Ivermectin and aged garlic extract combination evaluated.•Ivermectin reduced mitotic index, increased aberrant cells.•Aged garlic extract against IVM induced effects.