What disease-modifying therapy (DMT) for multiple sclerosis (MS) is safe to take while breastfeeding?

MS Disease-Modifying Therapies Compatible with Breastfeeding

Glatiramer acetate and interferon-beta are the safest and most evidence-supported DMTs for use during breastfeeding, with glatiramer acetate having the strongest real-world safety data in breastfed infants. 1, 2

First-Line Options During Breastfeeding

Glatiramer Acetate (Copaxone®)

• Most strongly recommended DMT for breastfeeding mothers based on real-world safety data from the COBRA study showing no increase in adverse events, hospitalizations, or antibiotic use in breastfed offspring compared to controls 2
• Available as 20 mg daily subcutaneous injection or 40 mg three times weekly 3
• Large polar molecule with minimal passage into breast milk 1
• Only MS DMT with FDA pregnancy category B designation, supporting its favorable safety profile 3
• Safety demonstrated in offspring breastfed for durations ranging from 6 to >574 days 2

Interferon-Beta

• Likely safe for breastfeeding due to large molecular size preventing clinically significant transfer into breast milk 1, 4
• Observational data support safety during lactation 4
• Can be continued or initiated while breastfeeding without interruption 1

Monoclonal Antibodies: Use with Caution

Natalizumab

• May be considered during breastfeeding with likely low transfer into breast milk 4
• For women with highly active MS requiring aggressive therapy, natalizumab represents a reasonable option 4
• Limited but emerging data suggest compatibility with breastfeeding 5, 4

Rituximab and Other Anti-CD20 Therapies

• Could be given before conception for women with highly active MS 4
• Limited data on use during breastfeeding itself, but monoclonal antibodies generally have low breast milk transfer 4

Medications to Avoid During Breastfeeding

Oral DMTs

• Dimethyl fumarate, teriflunomide, fingolimod, and other oral agents lack sufficient safety data for breastfeeding 1, 4
• Should be discontinued or avoided until breastfeeding is complete 4

Immune-Depleting Therapies

• Alemtuzumab and cladribine should not be used during breastfeeding due to their profound immunosuppressive effects 1

Corticosteroids for Acute Relapses

Prednisone Dosing Guidelines

• ≤20 mg daily: Continue breastfeeding without interruption 6
• >20 mg daily: Delay breastfeeding or discard milk for 4 hours after administration 7, 6
• Low-dose corticosteroids are compatible with breastfeeding per the American Academy of Pediatrics 7

Clinical Decision Algorithm

Step 1: Assess Disease Activity Risk

• Low relapse risk postpartum → Consider breastfeeding without DMT or with injectable DMTs 4
• High relapse risk → Strongly consider glatiramer acetate or interferon-beta 4
• Highly active MS → Consider natalizumab or cell-depleting therapy before conception 4

Step 2: Select Appropriate DMT

• First choice: Glatiramer acetate (strongest safety evidence) 2
• Second choice: Interferon-beta (likely safe, less robust data) 1, 4
• Third choice: Natalizumab (for highly active disease only) 4

Step 3: Encourage Breastfeeding

• Breastfeeding itself is associated with decreased postpartum relapse risk 4
• The benefits of maternal MS treatment with compatible DMTs outweigh potential risks to breastfed offspring 2

Key Pitfalls to Avoid

• Do not unnecessarily discontinue glatiramer acetate or interferon-beta when breastfeeding, as these are safe options and disease control is important 1, 2
• Do not use oral DMTs (dimethyl fumarate, fingolimod, teriflunomide) during breastfeeding due to insufficient safety data 4
• Do not discourage breastfeeding in women with MS, as it provides protective effects against postpartum relapses 4
• Do not administer high-dose corticosteroids (>20 mg prednisone daily) without timing considerations for breastfeeding 6