Laboratory Test Interactions
There are no reported laboratory test interactions.
Carcinogenesis, Mutagenesis, Impairment of Fertility
Long-term studies in animals have not been performed to evaluate carcinogenic potential. Azithromycin has shown no mutagenic potential in standard laboratory tests: mouse lymphoma assay, human lymphocyte clastogenic assay, and mouse bone marrow clastogenic assay.
Teratogenic Effects. Pregnancy Category B
Reproduction studies have been performed in rats and mice at doses up to moderately maternally toxic dose levels (i.e., 200 mg/kg/day). These doses, based on a mg/m2 basis, are estimated to be 4 and 2 times, respectively, the human daily dose of 500 mg.
With regard to the MAC treatment dose of 600 mg daily, on a mg/m2/day basis, the doses in rats and mice are approximately 3.3 and 1.7 times the human dose, respectively.
With regard to the MAC prophylaxis dose of 1200 mg weekly, on a mg/m2/day basis, the doses in rats and mice are approximately 2 and 1 times the human dose, respectively.
No evidence of impaired fertility or harm to the fetus due to azithromycin was found. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, azithromycin should be used during pregnancy only if clearly needed.