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Sulfamethoxazole / trimethoprim Pregnancy and Breastfeeding Warnings

Sulfamethoxazole / trimethoprim is also known as: Bactrim, Bactrim DS, Bactrim IV, Bactrim Pediatric, Bethaprim, Bethaprim Pediatric, Co-trimoxazole, Cotrim, Cotrim DS, Cotrim Pediatric, SMZ-TMP DS, Septra, Septra DS, Septra IV, Sulfatrim, Sulfatrim Pediatric, Uroplus, Uroplus DS

Medically reviewed on Dec 15, 2017

Sulfamethoxazole / trimethoprim Pregnancy Warnings

Animal studies suggest that exposure to this combination drug during pregnancy may be associated with an increased risk of congenital malformations, particularly neural tube defects, cardiovascular malformations, urinary tract defects, oral clefts, and club foot. There are no controlled data in human pregnancy.

-Sulfonamides may cause jaundice and hemolytic anemia in the newborn.
-Sulfonamides may cause kernicterus in babies during the first month of life by displacing bilirubin from plasma albumin; therefore, they should be avoided during the last month of pregnancy.
-Trimethoprim may interfere with folic acid metabolism and animal experiments have shown that administration of very high doses during organ development may cause birth defects typical of folic acid antagonism; if this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, folic acid supplementation may be required.

AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.

US FDA pregnancy category D: There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

UK, US: Contraindicated
AU: Benefit should outweigh risk.

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

Comments:
-UK, US: Some manufacturers recommend that this drug should be used in pregnancy only if the benefit outweighs the risk; check the individual manufacturer product labeling for more information.
-AU, US: Some manufacturers list this drug in a less restrictive pregnancy category than those listed above; check the individual manufacturer product labeling for more information.
-Because this combination drug may interfere with folic acid metabolism, a folate supplement should be considered.

See references

Sulfamethoxazole / trimethoprim Breastfeeding Warnings

Some experts consider use of this combination drug acceptable when breastfeeding healthy, full-term infants after the newborn period; alternate agents are recommended in jaundiced, ill, stressed, or premature infants.

AU, UK: Use is not recommended.
US: Contraindicated

Excreted into human milk: Yes (sulfamethoxazole, trimethoprim)

Comments:
-US: Some manufacturers recommend that this drug should be used in nursing mothers only if the benefit outweighs the risk rather than contraindicated; check the individual manufacturer product labeling for more information.
-Levels of trimethoprim and sulfamethoxazole in breast milk are approximately 2% to 5% of the recommended daily dose for infants over 2 months of age. Although the quantity ingested by a breastfed infant is small, it is recommended that the benefit should outweigh the risk to the infant. Consideration should be given to the age of the infant.
-Caution is recommended, especially if the infant is premature, ill, jaundiced, or stressed (risk of bilirubin displacement and kernicterus).
-This drug combination should be avoided while breastfeeding a G6PD-deficient infant.
-This drug combination is considered compatible with breastfeeding by the American Academy of Pediatrics if the infant is healthy and full-term.

See references

References for pregnancy information

  1. Cerner Multum, Inc. "Australian Product Information." O 0
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. "Product Information. Sulfamethoxazole-Trimethoprim (sulfamethoxazole-trimethoprim)." SICOR Pharmaceuticals Inc, Irvine, CA.

References for breastfeeding information

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT." ([cited 2013 -]):
  4. "Product Information. Sulfamethoxazole-Trimethoprim (sulfamethoxazole-trimethoprim)." SICOR Pharmaceuticals Inc, Irvine, CA.

Further information

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

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