[Placental permeability for rifampicin].

Albino rats were exposed to rifampicin inhalations for a prolonged period of time (during gravidity). It was found that the antibiotic penetrated through the placental barrier and its levels in the fetus were proportional to its content in the air inhaled. At later gravidity periods rafampicin absorption in albino rats increased and in parallel its levels in the ovum also increased. The exposure of albino rats to rifampicin inhalations during the whole period of their gravidity in concentrations lower than the Limac (the limit of the acute effect with respect to the general toxic parameters) did not affect the structure of the placenta and its permeability by the antibiotic.