Is Plavix (clopidogrel) safe during breastfeeding?

Clopidogrel (Plavix) During Breastfeeding

Clopidogrel (Plavix) should not be used during breastfeeding; alternative anticoagulants such as warfarin, unfractionated heparin (UFH), or low molecular weight heparin (LMWH) are recommended as safer options. 1

Safety Concerns with Clopidogrel During Breastfeeding

The American Society of Hematology (ASH) and American College of Chest Physicians (ACCP) guidelines provide clear recommendations regarding anticoagulant use during breastfeeding:

• There is no specific data on clopidogrel safety during breastfeeding
• Both guidelines recommend against using direct oral anticoagulants in breastfeeding women 1
• Clopidogrel's FDA label states: "It is not known if clopidogrel passes into your breast milk. A decision should be made with your healthcare provider to avoid or discontinue breastfeeding when continuing clopidogrel tablets is needed" 2

Recommended Anticoagulant Options During Breastfeeding

The following medications are considered safe during breastfeeding:

Strongly Recommended (Grade 1A/1B evidence):

• Warfarin/acenocoumarol: Highly protein-bound, polar, and non-lipophilic, with minimal transfer into breast milk 1
• Unfractionated heparin (UFH): Does not pass into breast milk due to large size and negative charge 1
• Low molecular weight heparin (LMWH): Minimal excretion into breast milk (0.006-0.037 IU/mL) with limited oral bioavailability 1
• Danaparoid: Very low anti-FXa activity in breast milk (<0.07 IU/mL) with negligible risk 1

Conditionally Recommended:

• Low-dose aspirin (<100 mg/day): Generally considered safe during breastfeeding 1

Not Recommended:

• Direct oral anticoagulants (including clopidogrel): Both ASH and ACCP strongly recommend against their use 1
• Fondaparinux: Alternative anticoagulants are suggested instead 1

Rationale for Recommendations

The recommendations against clopidogrel during breastfeeding are based on:

1. Lack of safety data: Insufficient evidence regarding clopidogrel transfer into breast milk and potential effects on breastfed infants
2. Availability of safer alternatives: Several well-studied anticoagulants with established safety profiles during breastfeeding
3. Risk-benefit assessment: When equally effective alternatives exist with better safety profiles, they should be preferred

Clinical Approach

When a breastfeeding woman requires anticoagulation:

1. Assess indication: Determine why anticoagulation is needed (VTE, stroke prevention, etc.)
2. Select appropriate agent:
   • For most indications: Choose warfarin, UFH, or LMWH
   • Consider patient-specific factors (e.g., ability to perform INR monitoring for warfarin, tolerance of injections for LMWH)
3. Monitor: Watch for any unusual bleeding or bruising in the infant
4. Reassess: Periodically evaluate the continued need for anticoagulation

Important Considerations

• The benefits of breastfeeding are significant and should be preserved when possible by selecting medications compatible with breastfeeding 3, 4
• The risk of maternal bleeding complications must be balanced against the risk of exposing the infant to medication through breast milk
• While recent case reports suggest rivaroxaban may have acceptable safety profiles (milk-to-plasma ratios of 0.27-0.32 and relative infant doses <1.3%), this evidence is preliminary and insufficient to change current guideline recommendations 5

In summary, when anticoagulation is required during breastfeeding, warfarin, UFH, or LMWH should be selected over clopidogrel based on current evidence and guidelines.