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Propafenone Pregnancy and Breastfeeding Warnings

Propafenone is also known as: Rythmol, Rythmol SR

Medically reviewed on Jul 19, 2018

Propafenone Pregnancy Warnings

This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus.

US FDA pregnancy category: C

Animal studies have revealed increased post-implantation loss at a dose approximately equal to one-third the maximum recommended human dose (MRHD) on a mg/m2 basis. Animal studies have also revealed increased maternal death at a dose equivalent to the MRHD on a mg/m2 basis. There are no controlled data in human pregnancy.

This drug has caused a reversible, short-term decrease (within normal range) in sperm count, which could affect fertility.

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

Propafenone Breastfeeding Warnings

Limited data suggests that maternal doses up to 900 mg/day produce low levels in milk (up to 0.1% of the maternal weight-adjusted dosage) and are not expected to cause adverse effects in breastfed infants, especially if the infant is older than 2 months.

A decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother.

Excreted into human milk: Yes

Comments: The effects in the nursing infant are unknown.

See references

References for pregnancy information

  1. "Product Information. Rythmol SR (propafenone)." GlaxoSmithKline, Research Triangle Park, NC.
  2. "Product Information. Rhythmol (propafenone)." Knoll Pharmaceutical Company, Whippany, NJ.

References for breastfeeding information

  1. 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 -]):
  2. "Product Information. Rythmol SR (propafenone)." GlaxoSmithKline, Research Triangle Park, NC.
  3. "Product Information. Rhythmol (propafenone)." Knoll Pharmaceutical Company, Whippany, NJ.

Further information

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

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