Is Disopyramide safe while breastfeeding?

Here is what NIH LactMed, the U.S. National Library of Medicine's authority on medicines and breastfeeding, reports about Disopyramide. This is a summary of that source — not our own verdict.

Effects on the breastfed infant

There are reports of two infants who were breast-fed without complications during maternal disopyramide use of 500 to 600 mg daily effect.[ 1 , 2 ] Infant symptoms of crying and restlessness after meals thought by one mother to be caused by disopyramide in breastmilk were judged to be unrelated by the examining physicians.[ 3 ]

Effects on milk supply

Relevant published information was not found as of the revision date.

Levels in milk

Maternal Levels. In one report, a maternal dose of 200 mg orally 3 times a day produced milk levels of 2.6 to 5.7 mg/L and N-monodesalkyldisopyramide (NMD) levels of 1.8 to 4.8 mg/L during the days 4 to 17 postpartum.[ 1 ] A maternal disopyramide dose of 100 mg orally 5 times daily resulted in milk levels of 1.4 and 1.7 mg/L 3 hours after a dose on days 2 and 16 postpartum; metabolite levels were not measured.[ 2 ] The amounts in milk represent an infant dosage of about 2.5 to 3% of the maternal weight-adjusted dosage. A mother taking 200 mg of disopyramide twice daily had milk levels of 0.58 mg/L before a dose and 0.98 mg/L at 3.5 hours after a dose.[ 3 ] The amounts in milk represent an infant dosage of about 1.3 to 2.2% of the maternal weight-adjusted dosage. A woman taking 450 mg of disopyramide orally every 8 hours had milk levels of 2.6 to 4.4 mg/L at 0, 2, 4 and 8 hours after the dose, with the highest level reported 4 hours after the dose. Milk N-monodesalkyldisopyramide (NMD) levels ranged from 9.6 to 12.3 mg/L, with the highest level at 2 hours after the dose.[ 4 ] The peak disopyramide and NMD levels represent an infant dosage of about 3 and 8% of the maternal weight-adjusted dosages, respectively. One mother (time postpartum not stated) took a single dose of disopyramide 100 mg orally. The highest milk level was 0.64 mg/L at 3 and 4 hours after the dose. By 12 hours after the dose, the milk level had fallen to 0.11 mg/L. The authors estimated that an exclusively breastfed infant would receive 3% of the maternal weight-adjusted dosage of disopyramide; however, metabolite levels were not measured.[ 5 ] Infant Levels. A mother took disopyramide 200 mg orally 3 times a day. After 28 days of breastfeeding, the infant had a plasma disopyramide level of 0.5 mg/L (about 12.5% of maternal serum level) and no detectable NMD.[ 1 ] The mother of a breastfed infant was taking a disopyramide dose of 100 mg orally 5 times daily. Disopyramide was undetectable ( 0.5 mg/L

Source: NIH LactMed (National Library of Medicine).

Educational summary of an authoritative source — not medical advice. Never start, stop, or change a medicine while breastfeeding without confirming with your doctor.