8 USE IN SPECIFIC POPULATIONS
Limited published data on epinephrine use in pregnant women are not sufficient to determine a drug-associated risk for major birth defects or miscarriage. However, there are risks to the mother and fetus associated with epinephrine use during labor or delivery, and risks due to untreated hypotension associated with septic shock (see Clinical Considerations). In animal reproduction studies, epinephrine demonstrated adverse developmental effects when administered to pregnant rabbits (gastroschisis), mice (teratogenic effects, embryonic lethality, and delayed skeletal ossification), and hamsters (embryonic lethality and delayed skeletal ossification) during organogenesis at doses approximately 15 times, 3 times and 2 times, respectively, the maximum recommended daily intramuscular or subcutaneous dose (see Data).
All pregnancies have a background risk of birth defects, loss, or other adverse outcomes. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. 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.
Disease-associated maternal and/or embryo/fetal risk
Hypotension associated with septic shock is a medical emergency in pregnancy which can be fatal if left untreated. Delaying treatment in pregnant women with hypotension associated with septic shock may increase the risk of maternal and fetal morbidity and mortality. Do not withhold life-sustaining therapy for a pregnant woman.
Labor or Delivery
Epinephrine usually inhibits spontaneous or oxytocin induced contractions of the pregnant human uterus and may delay the second stage of labor. Avoid epinephrine during the second stage of labor. In dosage sufficient to reduce uterine contractions, the drug may cause a prolonged period of uterine atony with hemorrhage. Avoid epinephrine in obstetrics when maternal blood pressure exceeds 130/80 mmHg.
Although epinephrine improves maternal hypotension associated with anaphylaxis, it may result in uterine vasoconstriction, decreased uterine blood flow, and fetal anoxia.
In a study in pregnant rabbits administered 1.2 mg/kg/day epinephrine (approximately 15 times the maximum recommended intramuscular or subcutaneous dose on a mg/m2 basis) subcutaneously during organogenesis (on days 3 to 5, 6 to 7 or 7 to 9 of gestation), epinephrine caused teratogenic effects (including gastroschisis). Animals treated on days 6 to 7 had decreased number of implantations.
In a teratology study, pregnant mice were subcutaneously administered epinephrine (0.1 to 10 mg/kg/day) on Gestation Days 6 to 15. Teratogenic effects, embryonic lethality, and delays in skeletal ossification were observed at approximately 3 times the maximum recommended intramuscular or subcutaneous dose (on a mg/m2 basis at maternal subcutaneous dose of 1 mg/kg/day for 10 days). These effects were not seen in mice at approximately 2 times the maximum recommended daily intramuscular or subcutaneous dose (on a mg/m2 basis at a subcutaneous maternal dose of 0.5 mg/kg/day for 10 days).
Subcutaneous administration of epinephrine to pregnant hamsters at a dose of 0.5 mg/kg/day (approximately 2 times the maximum recommended intramuscular or subcutaneous dose on a mg/m2 basis) on Gestation Days 7 to 10 resulted in delayed skeletal ossification and a reduction in litter size.
There is no information regarding the presence of epinephrine in human milk, or the effects of epinephrine on the breastfed infant or on milk production. However, due to its poor oral bioavailability and short half-life, epinephrine exposure is expected to be very low in the breastfed infant. The lack of clinical data during lactation precludes a clear determination of the risk of epinephrine to a breastfed infant.
8.5 Geriatric Use
Clinical studies of epinephrine for the treatment of hypotension associated with septic shock did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.