Here is my professional opinion:

The Relative Infant Dose (RID) of Methergine is only 2%, the half life is only 20-30 minutes, and peak concentration in breast milk is about 0.5 to 3 hours.
The pharmacokinetic data do not appear to support a 12 hour delay in breastfeeding.
The 12 hour breastfeeding withhold recommendation is overly cautious, especially for acute dosing.
To be very cautious, six hours would be more appropriate for chronic dosing just to make sure there is even less than the minimal amount that would get into breast milk otherwise.
The drug has been used in breastfeeding women to control bleeding in the past without any adverse infant effects reported.
If only one or several acute doses are given, the benefits of breastfeeding far outweigh the risk of the drug and the risks of not breastfeeding.

I contacted pretty much everyone involved at the FDA and even sent a copy of my article: Medications and Breastfeeding: Current Concepts
If anyone wants a copy of my article, please email me at: [log in to unmask]
They were not willing to listen or to take into consideration a benefit-risk analysis of the benefits of breastfeeding and the drug and the risks of the drug and the risks of not breastfeeding.

Frank J. Nice, RPh, DPA, CPHP
 		 	   		  
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