Is Pindolol safe while breastfeeding?
Here is what NIH LactMed, the U.S. National Library of Medicine's authority on medicines and breastfeeding, reports about Pindolol. This is a summary of that source — not our own verdict.
Effects on the breastfed infant
Relevant published information on pindolol was not found as of the revision date. A study of mothers taking beta-blockers during nursing found a numerically, but not statistically significant increased number of adverse reactions in those taking any beta-blocker. Although the ages of infants were matched to control infants, the ages of the affected infants were not stated. None of the mothers were taking pindolol.[ 3 ]
Effects on milk supply
Relevant published information on the effects of beta-blockade or pindolol during normal lactation was not found as of the revision date. A study in 6 patients with hyperprolactinemia and galactorrhea found no changes in serum prolactin levels following beta-adrenergic blockade with propranolol.[ 4 ]
Levels in milk
The excretion of beta-adrenergic blocking drugs into breastmilk is largely determined by their protein binding. Those with low binding are more extensively excreted into breastmilk.[ 1 ] Accumulation of the drugs in the infant is related to the fraction excreted in urine. With 60% protein binding, 40% renal excretion and a half-life of 3 hours, pindolol presents moderately low risk for accumulation in infants. Pindolol is administered as a racemic mixture, but the (-)- S enantiomer has much more activity than the (+)- R enantiomer.[ 2 ] Maternal Levels. Three women were receiving pindolol 10 mg every 12 hours during pregnancy and postpartum. A single breastmilk sample was collected from each mother on the day of delivery at 11, 12 or 14 hours after the previous pindolol dose. The 2 pindolol enantiomers were measured separately in milk, with (-)- S -pindolol concentration averaging 3.1 mcg/L (range 1.5 to 3.9 mcg/L) and (+)- R -pindolol averaging 1.9 mcg/L (range 1.2 to 4.2 mcg/L).[ 2 ] Using the AUC and milk/plasma ratio values reported, a fully breastfed infant would receive an average of 0.36% of the maternal weight-adjusted dosage of pindolol. Infant Levels. Relevant published information was not found as of the revision date.
Alternatives LactMed lists
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.