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Norfloxacin Pregnancy and Breastfeeding Warnings

Norfloxacin is also known as: Noroxin

Norfloxacin Pregnancy Warnings

This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus; according to some authorities, use is contraindicated.

AU TGA pregnancy category: B3
US FDA pregnancy category: C

Animal studies have revealed evidence of embryolethality at high doses; embryonic loss was observed in cynomolgus monkeys at doses 10 times the maximum daily human dose (150 mg/kg/day) with Cmax in monkeys about 2 to 3 times Cmax in humans. Animal studies have failed to reveal evidence of teratogenicity in rats, rabbits, mice, and monkeys at 6 to 50 times the maximum daily human dose (100 to 800 mg/kg/day). This drug passes into umbilical blood and amniotic fluid. There are no controlled data in human pregnancy; however, surveillance studies have not reported an increased risk of major birth defects.

Of 549 cases reported by the European Network of Teratology Information Services involving fluoroquinolone exposure (including norfloxacin), congenital malformations were reported in 4.8%; however, this was not higher than the background rate.

In the US Michigan Medicaid surveillance study of 229,101 pregnancies, major birth defects were reported in 5 of 139 exposed neonates.

Berkovitch and colleagues reviewed 35 pregnancies in women who received norfloxacin or ciprofloxacin during the first trimester for urinary tract infection. No malformations were observed among the infants of these women. When compared to infants not exposed to quinolones, there was no difference in the acquisition of developmental milestones and no joint problems or walking delays.

Cartilage damage and arthropathy have been reported in immature animals of various species giving rise to concern over possible toxic effects on human fetal bone formation. Because safer alternatives are generally available, some experts consider fluoroquinolones contraindicated during pregnancy, especially during the first trimester.

AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.

US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

See references

Norfloxacin Breastfeeding Warnings

LactMed: Use is considered acceptable with monitoring of the infant for possible effects on the gastrointestinal flora (e.g., diarrhea or candidiasis [thrush, diaper rash]).
-According to some authorities, use is contraindicated.
-According to other authorities, a decision should be made to discontinue breastfeeding or discontinue the drug (at least 24 to 48 hours before restarting breastfeeding), taking into account the importance of the drug to the mother.

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

-Other fluoroquinolone antibiotics are excreted into human milk; it is likely that this drug is also.
-The effects in the nursing infant are unknown; potential risk of serious side effects in the nursing infant.

Cartilage erosion and arthropathy have been observed in immature animals giving rise to concern over toxic effects in the developing joints of nursing infants; however, some studies suggest risk is low. Absorption of the small amounts of fluoroquinolones in milk may be blocked by the calcium in milk; data insufficient to prove or disprove. Serum levels, milk levels, and oral bioavailability of this drug are the lowest of any fluoroquinolone; risk to the nursing infant should be minimal.

This drug was not detectable in milk at any time up to 6 hours after a single 200 mg oral dose; milk levels have not been measured after multiple doses.

See references

References for pregnancy information

  1. Ramakrishnan K, Scheid DC "Diagnosis and management of acute pyelonephritis in adults." Am Fam Physician 71 (2005): 933-42
  2. Briggs GG, Freeman RK, Yaffe SJ.. "Drugs in Pregnancy and Lactation. 5th ed." Baltimore, MD: Williams & Wilkins (1998):
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  4. "Product Information. Noroxin (norfloxacin)." Merck & Co, Inc, West Point, PA.
  5. Cerner Multum, Inc. "Australian Product Information." O 0
  6. Berkovitch M, Pastuszak A, Gazarian M, Lewis M, Koren G "Safety of the new quinolones in pregnancy." Obstet Gynecol 84 (1994): 535-8

References for breastfeeding information

  1. "Product Information. Noroxin (norfloxacin)." Merck & Co, Inc, West Point, PA.
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. Briggs GG, Freeman RK, Yaffe SJ.. "Drugs in Pregnancy and Lactation. 5th ed." Baltimore, MD: Williams & Wilkins (1998):
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  5. Melbourne: Therapeutic Guidelines Limited "eTG complete [Online] Available from: URL:" ([2014, Nov -]):
  6. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL:" ([cited 2013 -]):

Further information

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