Tobi and Pregnancy
Although Tobi has not been adequately studied in pregnant women, the drug did cause birth defects when given as an injection to pregnant animals. However, Tobi is an inhaled solution and only a small amount is expected to reach the bloodstream. Although this drug has a pregnancy Category D rating, it may still be given if the benefits outweigh the risks.
Tobi® (tobramycin inhalation solution) is a prescription medication approved for treating a Pseudomonas aeruginosa infection in people with cystic fibrosis. Tobi may harm a fetus if used by a pregnant woman.
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when specific medicine is taken during pregnancy. Tobi is classified as a pregnancy Category D medicine.
Pregnancy Category D is a classification given to medicines that have been shown to present a risk to the fetus in studies of pregnant women but may still offer benefits that outweigh the risks the drug presents. A pregnancy Category D medicine may still be given to a pregnant woman if her healthcare provider believes that the benefits to the woman outweigh the possible risks to her unborn child.
Tobi has not been adequately studied in pregnant women. In animal studies, tobramycin (the active ingredient in Tobi) did not cause birth defects when given as an injection to pregnant rats and rabbits. However, it did cause kidney problems in both the mother rats and unborn rats when it was given in high doses.
Tobi belongs to a group of antibiotic medicines known as aminoglycosides. All aminoglycosides have the potential to cause damage to the inner ear, which could lead to hearing loss and balance problems. Another aminoglycoside (streptomycin) has been reported to cause irreversible deafness in both ears in children whose mothers were treated with the medicine while pregnant.
It is important to note that Tobi is an inhaled antibiotic, and very little of the medicine is expected to reach the bloodstream with normal use. In addition, researchers who have studied the possible effects of aminoglycosides on a fetus when taken during pregnancy have concluded that the risk for deafness is small.