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Omadacycline Pregnancy and Breastfeeding Warnings

Medically reviewed by Last updated on May 16, 2023.

Omadacycline is also known as: Nuzyra

Omadacycline Pregnancy Warnings

The manufacturer makes no recommendation regarding use during pregnancy.

US FDA pregnancy category: Not assigned.

Risk summary: This drug may cause harm to the embryo or fetus; like other tetracycline-class agents, it may cause deciduous tooth discoloration and reversible bone growth inhibition when used during the second and third trimester of pregnancy; insufficient data available on use of this drug in pregnant women to inform a drug-related risk.

-If this drug is used during the second or third trimester of pregnancy, the patient should be apprised of the potential harm to the fetus.
-Females of Reproductive Potential: Patients should be advised to use effective contraception during therapy.

Animal studies have revealed evidence of embryofetal lethality, teratogenicity, and embryofetal toxicity. IV infusion to pregnant rats during organogenesis (at doses of 5 to 80 mg/kg/day) led to maternal lethality at 80 mg/kg/day, increased embryofetal lethality and fetal malformations (whole body edema) at 60 mg/kg/day (7 times the clinical AUC), dose-dependent fetal body weight reductions at all doses, and delayed skeletal ossification at doses as low as 10 mg/kg/day; IV infusion to pregnant rabbits during organogenesis (at doses of 5, 10, or 20 mg/kg/day) led to maternal lethality and body weight loss and embryofetal lethality, congenital skeletal malformations, and reduced fetal weight at 20 mg/kg/day (7 times the clinical AUC), dose-related incidence of cardiac and lung malformations at 10 and 20 mg/kg/day, and the fetal no-adverse-effect-level was 5 mg/kg/day (at about 1.2 times the clinical steady-state AUC). Animal studies indicate tetracyclines cross the placenta, are found in fetal tissues, and can have toxic effects on developing fetus (often related to delayed skeletal development); embryotoxicity has been observed in animals treated early in pregnancy. There are no controlled data in human pregnancy.

In rat studies, injury to the testis and reduced sperm counts and motility were observed in male rats after treatment with this drug; in female rats, this drug affected fertility parameters, causing reduced ovulation and increased embryonic loss at intended human exposures.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

See references

Omadacycline Breastfeeding Warnings

The amount of this drug excreted into breast milk is unknown, but the drug is only about 35% absorbed orally under optimal conditions, and is probably less from milk due to its calcium content.

LactMed: As a precaution, prolonged or repeat courses should be avoided during breastfeeding.
-According to some authorities: Breastfeeding is not recommended during use of this drug and for 4 days after the last dose.

Excreted into human milk: Unknown
Excreted into animal milk: Data not available

-No data available on the use of this drug during breastfeeding.
-The effects in the nursing infant are unknown; potential for serious side effects (including tooth discoloration, inhibition of bone growth)
-According to some experts: If breastfed, the infant should be monitored for possible effects on the gastrointestinal flora (e.g., diarrhea, candidiasis [e.g., thrush, diaper rash], or rarely, blood in the stool indicating possible antibiotic-associated colitis).
-Tetracyclines are excreted into human milk; extent of absorption of tetracyclines (including this drug) by nursing infants not known.
-Patients should be advised not to breastfeed during use of this drug and for 4 days after the last dose as other antibacterial agents are available to treat nursing women and due to the potential for serious side effects.

See references

References for pregnancy information

  1. Product Information. Nuzyra (omadacycline). Paratek Pharmaceuticals, Inc. 2018.

References for breastfeeding information

  1. Product Information. Nuzyra (omadacycline). Paratek Pharmaceuticals, Inc. 2018.
  2. National Library of Medicine (US). Drugs and Lactation Database (LactMed) 2019.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.