If someone suggests that you should wean temporarily while taking a certain medication, keep in mind that the potential risk of mom’s use of medication while breastfeeding needs to be weighed against several factors:
- The known risks of formula feeding, including allergy, increased illness, etc. Many of the risks of formula feeding are not apparent for many years.
- The risk of baby not going back to the breast. Many babies have a hard time returning to breastfeeding after temporary weaning.
- The risk to mom’s milk supply. Milk supply may be compromised since pumps do not provide the same stimulation to supply as does a nursing baby. For the rare times when temporary weaning is needed, see this information on maintaining milk supply when baby is not nursing.
Keep in mind that it is not appropriate to use pregnancy risk categories to determine the risk of a drug to a breastfeeding mother and her baby, since the entry of drugs into human milk is different than the entry of drugs across the placenta.
It is not uncommon to see doctors using the Physicians Desk Reference for information on medications and nursing. This reference contains the package inserts from the pharmaceutical manufacturers. Almost across the board, they indicate that the medication should not be taken while pregnant or breastfeeding. The warning statements they use are designed to protect themselves from lawsuits. The information in the PDR is based on the manufacturer’s studies on the product, but not other studies that have been done. In general the manufacturers have done no studies on lactating women, and thus say that there is no information (even if studies have been done by others).
Many doctors also have access to the USPDI (US Pharmacoepia Drug Information), which tends to have more accurate information than the PDR about studies done on the drug and available information about transfer into milk. If you don’t have access to the “gold standard” books (below) on medications and breastfeeding, this reference is generally a better choice than the PDR.
Our favorite reference is Medications and Mothers’ Milk by Thomas Hale, PhD, which is updated every couple of years. This is a must-have for anyone working with breastfeeding mothers or breastfeeding mothers who frequently need information on medications.
One of the best online sources for information on breastfeeding and medications is the LactMed Database (which became available in 2006), maintained by the National Library of Medicine. If your doctor does not know about this resource, spread the word!
Talking to baby’s pediatrician (in addition to your own doctor) can also be a good idea. Baby’s doctor will generally know more about the effects of medications on infants and young children, and whether a medication is typically given directly to infants or young children. Baby’s doctor will also be aware of any particular health concerns that your baby has with respect to a particular medication.
If you’re having problems finding the information you need, contact a local lactation consultant, or breastfeeding counselor.
Good information on breastfeeding and medications can be found here:
Medications and Mothers’ Milk by Thomas Hale, PhD
The InfantRisk Center (headed by Dr. Thomas Hale in the US) has a phone helpline (1-806-352-2519) and additional information on medication use during pregnancy and breastfeeding. They also have smartphone apps available.
MotherRisk (operated by the Hospital for Sick Children in Toronto, Canada) has a phone helpline (1-877-439-2744) and additional information on medication use during pregnancy and breastfeeding.
Drugs in Breastmilk from The Breastfeeding Network (UK) has a phone helpline (0844 412 4665) and additional information on medication in breastfeeding mothers.
Academy of Breastfeeding Medicine Clinical Protocol #15: Analgesia and Anesthesia for the Breastfeeding Mother