Prenatal exposure to anti-tubercular drugs and postnatal effect on growth, development and cognitive ability in rats

The effect of prenatal exposure to antitubercular drugs in therapeutic and double therapeutic doses on postnatal developments was studied in albino rats of Wistar strain. Seven groups with six female rats each were taken for the study and were allowed to mate with male in the ratio of (2:1). The drugs isoniazid 27 and 54mg/kg b.w. p.o., ethambutol 144 and 288mg/kg b.w. p.o., rifampin 54 and 108mg/kg b.w. p.o. were administered to each group from the day of pregnancy till parturition. Control group was administered with distilled water (1ml/kg). Litters of the respective groups were studied for litter size; body weight; physical development i.e. eye opening, pinna detachment, incisor eruption; behavioral development i.e. righting reflex, negative geotaxis, ascending wire mesh; motor development i.e. rotarod and cognitive function i.e. elevated plus maze, Hebb-William maze and step-down (passive avoidance). The results obtained indicate that the prenatal exposure to therapeutic dose of rifampin and double therapeutic dose of rifampin, isoniazid and ethambutol affect the postnatal growth, development and cognitive ability. Hence, the study suggests that potential benefit risk ratios to be considered for their use in pregnancy.