What is the recommended treatment for a breastfeeding mother with influenza, specifically regarding the use of Tamiflu (oseltamivir)?

Oseltamivir (Tamiflu) Use During Breastfeeding

Breastfeeding mothers with influenza should receive oseltamivir 75 mg twice daily for 5 days and continue breastfeeding without interruption. 1

Primary Recommendation

Oseltamivir is the preferred antiviral agent for breastfeeding mothers with influenza, and breastfeeding should not be discontinued. 1 The American Academy of Pediatrics explicitly states that none of the antiviral agents, including oseltamivir, are reasons to discontinue breastfeeding. 1

Dosing for Breastfeeding Mothers

• Treatment dose: 75 mg orally twice daily for 5 days 1, 2
• Initiate within 48 hours of symptom onset for maximum benefit, though later initiation can still provide clinical benefit 3, 2
• Can be taken with or without food, though administration with meals may improve gastrointestinal tolerability 1, 2

Safety Profile in Lactation

• Oseltamivir and its active metabolite (oseltamivir carboxylate) are present in breast milk but at significantly lower concentrations than therapeutic levels for infants 4
• Pharmacokinetic studies demonstrate that breast milk concentrations are lower and appear later than plasma concentrations 4
• The active metabolite concentrations in breast milk are well below what would be considered therapeutic in infants 4

Breastfeeding Management During Maternal Influenza

• Direct breastfeeding should be encouraged even when the mother has confirmed influenza 1
• If the mother is too sick to breastfeed directly, she should pump and feed expressed breast milk 1
• Breastfeeding provides protective benefits against influenza through activation of innate antiviral mechanisms, specifically type 1 interferons 1
• Breast milk from mothers vaccinated during the third trimester contains higher levels of influenza-specific immunoglobulin A 1

Critical Clinical Considerations

• Do not delay treatment while waiting to determine breastfeeding status—the benefits of treating maternal influenza outweigh any theoretical risks to the nursing infant 1
• Oseltamivir is FDA-approved for infants as young as 2 weeks of age for treatment, further supporting its safety profile in the breastfeeding context 1, 2
• The drug has simple, uncomplicated pharmacology and lacks potential for significant drug-drug interactions 5

Common Pitfalls to Avoid

• Never advise discontinuation of breastfeeding due to maternal oseltamivir use—this is explicitly contraindicated by AAP guidelines 1
• Do not withhold oseltamivir treatment from breastfeeding mothers due to concerns about infant exposure through breast milk 1
• Do not delay treatment beyond 48 hours when possible, as earlier initiation is associated with better outcomes 3, 2

Tolerability

• The most common adverse effects are nausea (12-15%) and vomiting (2.5-2.7%), which are mild, transient, and reduced when taken with food 6, 5, 7
• Serious adverse events are rare (1.3% in clinical trials, similar to placebo at 1.2%) 5