Use in Pregnancy & Lactation: Reproduction studies in rats and rabbits using acetylcysteine dosages up to 17 times the usual human dosage has not revealed evidence of impaired fertility or harm to the fetus.
There are no adequate and controlled studies to date using acetylcysteine in pregnant women, and the drug should be used during pregnancy only when clearly needed.
Since it is not known if acetylcysteine is distributed into human milk, the drug should be used with caution in nursing women.