Aztreonam

Contraindications

4 CONTRAINDICATIONS CAYSTON is contraindicated in patients with a known allergy to aztreonam. Contraindicated in patients with a known allergy to aztreonam. ( 4 )

Pregnancy & Breastfeeding

8.1 Pregnancy Risk Summary Available data on CAYSTON use in pregnant women is insufficient to inform a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes; however, systemic absorption of aztreonam following inhaled administration is expected to be minimal [see Clinical Pharmacology (12.3) ]. There are risks to the mother associated with cystic fibrosis in pregnancy (see Clinical Considerations ) . In animal reproduction studies with aztreonam for injection administered parenterally to pregnant rats and rabbits during organogenesis, there was no evidence of developmental toxicity. A peri/postnatal study in rats revealed no drug-induced changes in maternal, fetal, or neonatal parameters. The estimated background risk of major birth defects and miscarriage for the indicated population are unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Cystic fibrosis may increase the risk for preterm delivery. Data Animal Data No reproductive toxicity studies have been conducted with CAYSTON. However, studies were conducted with aztreonam for injection. No evidence of developmental toxicity has been shown in studies with pregnant rats and rabbits that received parenteral doses of aztreonam during organogenesis of up to 1800 and 1200 mg/kg/day, respectively. In rats receiving aztreonam for injection during late gestation and lactation at up to 1800 mg/kg/day, no drug induced changes in maternal, fetal or neonatal parameters were observed. These animal reproduction and developmental toxicity studies used parenteral routes of administration that would provide systemic exposures significantly greater than the average peak plasma levels measure