Medication and Lactation Compatibility
All too often parents are told by health care providers that a medication is incompatible with breastfeeding. Parents are not given the information from the respected resources that health care providers have access to, and breastfeeding is needlessly disrupted. Fortunately, there are publicly available resources that provide the information parents need and deserve to make informed decisions about medication and lactation compatibility. While there may not be large studies available looking at the effect of a medication on breastfeeding dyads for every medication, there are basic facts about all medications available that help determine the likelihood of an impact to the infant.
When assessing the compatibility of a medication with lactation the following factors are considered:
Maternal Plasma Concentration: Breast milk is synthesized directly from maternal plasma, so drugs that accumulate in maternal plasma in higher amounts will more readily transfer to breast milk.
Molecular Weight: The higher the molecular weight (over 300) the less able the drug is to pass into the breast milk. Drugs with molecular weight less than 800 can pass into breast milk.
Protein Binding: Drugs with high protein binding are unable to diffuse in significant amounts, making them less able to transfer into breast milk.
Drugs that actively pass the blood/brain barrier and are active in the Central Nervous System are more readily able to cross the blood/milk barrier.
How far past birth is the mother: In the first 72 hours postpartum there are large gaps in between the alveolar cells that would allow medications to more readily pass into the milk, although the low amounts of colostrum at this stage inhibit the amount of total drug ingested by virtue of the low volume consumed. It is also important to consider that a newborn may be more sensitive to a medication than an older infant would be.
Thankfully we do not have to actively stop and research this about every drug a parent considers taking because there are easily accessible reputable resources that look at all of this for us:
These three resources give us a lot of information about the medication, the information known about impact on breastfeeding babies, issues with milk supply, and alternative medications to consider. Here is a snapshot of the information for the medication Loratadine. Based on the information from all three sources you can see that this medication is compatible with lactation and you can be confident in your decision to use this medication.
With all of this information a parent can have an informed conversation with their health care provider to weigh the risks and benefits of a medication, and the available alternatives to make the decision that is right for them. Use these resources to make informed choices about your health care needs and to make sure that your breastfeeding relationship is not interrupted without good cause.
Note: A fabulous service from The Infant Risk Center is the ability to call them and actually discuss with a live knowledgeable person you individual situation. If you are every in doubt this is a great option!
