Management of Multiple Sclerosis in the Breastfeeding Mother

Table 1

Drug	Description	RID (%)	Clinical considerations
Interferons b1a and b1b	Immunomodulator and antineoplastic. Differs slightly from naturally occurring proteins. Anti-inflammatory properties	0.006	Limited data, probably compatible. Large MW. Relatively nontoxic
Glatiramer acetate	Immunosuppressant. Synthetic polypeptide of the amino acids L-alanine, L-glutamic acid, L-lysine, and L-tyrosine	—	No data, probably compatible. Large MW of 4,700 to 13,000 Daltons likely prohibits entry into breast milk. Toxicity unlikely
Mitoxantrone	Immunosuppressant and antineoplastic. DNA intercalating agent inhibits topoisomerase II	2–12	Limited data, hazardous. Large and half-life may lead to sequestering of drug in infant even with limited exposure via breast milk
Natalizumab	Recombinant monoclonal antibody	5	Limited data, probably compatible. Due to long time required to achieve steady state, actual concentration in breast milk is unknown
Fingolimod	Sphingosine-1-phosphate (SIP) modulator	—	No data, hazardous. High and levels in breast milk are expected to be low. Hazardous product due to bradycardia and hypotension as significant adverse effects. Hourly monitoring required
Dalfampridine	Potassium channel blocker improves skeletal muscle conduction—symptomatic treatment	—	Hazardous pending research. 2.6 L/kg. 96% oral bioavailability. Unknown if enters breast milk. Decide on case-by-case basis
Baclofen	Inhibits spinal cord reflexes resulting in reduced spasticity—symptomatic treatment	6.9	Limited data, probably compatible. Enters breast milk in small amounts. No adverse effects seen in infant
Dimethyl fumarate	Ester derivative of fumaric acid, immunosuppressant	—	No data, possibly hazardous. Low MW of 129 Daltons makes it likely to enter breast milk. Monitor infant for vomiting and diarrhea
Alemtuzumab	Recombinant DNA-derived humanized monoclonal antibody targets CD52 glycoprotein	—	No data, possibly hazardous. MW of 150 kD. Unlikely to enter milk due to large size
Teriflunomide	Pyrimidine synthesis inhibitor Immunomodulator	—	No data, hazardous. Extensive half-life and GI absorption. Likely present in milk. Due to toxicity in adults, caution advised during breastfeeding
Cladribine	Immunosuppressive agent causes apoptosis of lymphocytes	—	No data, hazardous. Penetrates CSF with doses 25% of plasma. Potentially enters milk. Withhold breastfeeding for 48 hours or longer if maternal renal dysfunction exists
Methylprednisolone	Corticosteroid. Anti-inflammatory agent	0.4–3	Limited data, probably compatible. Enters breast milk in very low amounts
Azathioprine	Derivative of mercaptopurine; metabolites halt DNA replication and purine synthesis. Immunosuppressive agent	0.07–0.3	Limited data, probably compatible. No adverse effects seen in infants. Monitor infant for signs of leukopenia, pancreatitis, and immunosuppression
Rituximab	Chimeric (human/mouse) monoclonal antibody targets CD20	—	No data, possibly hazardous. Large MW, unlikely to enter milk. Significant side effect profile
Daclizumab	Humanized monoclonal antibody targets IL-2 and CD25	—	Not known if enters milk but probably minimal. Hazardous pending research. Decide on case-by-case basis
Cyclophosphamide	Antineoplastic agent suppresses DNA synthesis	—	No data, hazardous. Enters breast milk. Reports of leukopenia in infants; withhold breastfeeding for 72 hours
Methotrexate	Inhibits dihydrofolate reductase and prevents DNA synthesis	0.1–0.9	Limited data, possibly hazardous. Enters into breast milk. Contraindicated in breastfeeding due to potential for serious side effects. Monitor infant for vomiting, diarrhea, and blood in the vomit, stool, or urine

RID = Relative Infant Dose, MW = molecular weight. = volume of distribution. MS = Multiple Sclerosis. IL = Interleukin. CD = Cluster of Differentiation. = FDA approved for MS Treatment.