Phenelzine and breastfeeding
We've been asked whether treatment with phenelzine is compatible with breastfeeding: it's a pre-birth enquiry, so no infant details. Mother is stable on this, and wants to know if she'll be able to breastfeed.
It's such an old drug that reliable published information on all aspects of its kinetics is limited, let alone milk levels! The data I've found so far, however, suggest that infant exposure would probably be low. Any relevant information or experience would be very helpful to us.
Phenelzine (Nardil) is an old monoamine oxidase inhibitor (MAO inhibitor). We do not have any data on the use of this product in breastfeeding women. But even if small amounts reached the infant, it might be enough to inhibit MAO in the child. Also, remember there are literally hundreds of severe drug-drug interactions with MAO inhibitors that could prove life threatening.
I would not suggest this mom use this product while breastfeeding. I think it is too risky for the infant.
Tom Hale Ph.D.
Thanks for the advice: I don't like recommending against breastfeeding, but I was not comfortable with this one.