In addressing neuromuscular blockade, anticholinesterases such as neostigmine or pyridostigmine are commonly employed. Their quaternary ammonium structure helps minimize transfer to breast milk.
However, studies indicate that repeated administrations of pyridostigmine for myasthenia gravis treatment result in approximately 0.1% of the maternal dose being transferred into breast milk. Additionally, anticholinergics like atropine and glycopyrrolate are utilized to reverse neuromuscular blockades. Although atropine is present in minimal quantities in breast milk, glycopyrrolate, another quaternary ammonium compound, exhibits reduced transfer to breast milk. Furthermore, sugammadex, known for its lack of metabolites and hydrophilic properties, is considered safe for lactating individuals.
There is a lack of data regarding the clinical utilization of flumazenil during breastfeeding. It is improbable to have negative effects on the breastfed infant. Thus, if the mother necessitates flumazenil, there is no grounds for ceasing breastfeeding. With a half-life of 54 minutes, refraining from breastfeeding for 4 to 5 hours following a dose should mitigate transfer to the infant.
Naloxone is excreted into breast milk in minimal quantities, and due to its very limited oral bioavailability, it remains undetectable in the plasma of breastfed infants. Consequently, the routine use of naloxone in combination products raises no breastfeeding-related concerns. However, in the event that naloxone is necessary for treating an opioid overdose, it is advisable for the mother to refrain from nursing until the opioid has sufficiently cleared from her system.
| Agent | Transfer into breast milk | Breastfeeding guidance |
|---|---|---|
| Neostigmine / pyridostigmine | Quaternary ammonium structure minimizes transfer; repeated pyridostigmine dosing for myasthenia gravis yields about 0.1% of the maternal dose in milk | Commonly employed for neuromuscular blockade reversal |
| Atropine | Present in minimal quantities | — |
| Glycopyrrolate | Quaternary ammonium compound with reduced transfer | — |
| Sugammadex | No metabolites and hydrophilic | Considered safe for lactating individuals |
| Flumazenil | No data on clinical use during breastfeeding; half-life 54 minutes | Improbable to affect the infant and no grounds to stop breastfeeding; withholding feeds for 4–5 hours after a dose should mitigate transfer |
| Naloxone | Minimal excretion into milk and very limited oral bioavailability; undetectable in the plasma of breastfed infants | No concern in routine combination products; if given for opioid overdose, withhold nursing until the opioid has sufficiently cleared |
