What are the recommendations for a lactating mother who becomes ill regarding continuation of breastfeeding, safe medications, and indications for temporarily stopping nursing?

Management of Illness in Breastfeeding Mothers

Breastfeeding should continue in nearly all maternal illnesses, as interruption poses greater risks to both mother and infant than the theoretical concerns about medication or pathogen transmission through breast milk. 1

General Principle: Continue Breastfeeding

• Most maternal illnesses are NOT contraindications to breastfeeding, and continuation provides protective antibodies to the infant against the mother's illness while preventing maternal complications like engorgement and mastitis. 2, 3

• The intercellular gaps in milk glands close soon after the immediate postpartum period, meaning drug passage into breast milk is minimal—far less than the placental transfer that occurs during cesarean sections, after which mothers are encouraged to breastfeed immediately. 1

• Interrupting breastfeeding carries significant risks: breast engorgement, blocked ducts, mastitis requiring antibiotics, infant refusal of bottles, infant dehydration (especially in exclusively breastfed babies), and exposure to cow's milk protein in allergic infants. 1

Medication Safety During Breastfeeding

Most Medications Are Compatible

• The vast majority of medications are compatible with breastfeeding, with only a limited number of contraindicated agents for which appropriate substitutes can usually be found. 1

• Use LactMed (Drugs and Lactation Database) from the National Library of Medicine as the most comprehensive resource for medication safety during breastfeeding. 1

Specific Medication Classes

Safe medications during breastfeeding include:

• 5-ASA preparations and sulfasalazine: Low concentrations in breast milk, considered safe. 1

• Corticosteroids: Found in low concentrations in breast milk; no need to discard milk or avoid feeding within 4 hours of administration. 1

• Thiopurines (azathioprine, 6-mercaptopurine): Generally acceptable throughout breastfeeding, with studies showing no detectable metabolites in infant serum and age-appropriate development. 1

• Anti-TNF therapy (infliximab, adalimumab): No or low levels detected in breast milk, with undetectable or very low levels in infant sera; no significant increase in infant infections reported. 1

• Antibiotics for mastitis: Cephalexin, dicloxacillin, amoxicillin/clavulanic acid, clindamycin, and erythromycin/azithromycin are all safe during breastfeeding. 4

Medications to avoid:

• Methotrexate: The least preferred option during breastfeeding due to detectable levels in milk and potential tissue accumulation in neonates. 1

• Tetracyclines and fluoroquinolones: Generally avoided due to potential impacts on infant development. 4

Specific Infectious Illness Scenarios

Viral Infections

• Influenza: Breastfeeding is strongly encouraged as it activates innate antiviral mechanisms and provides influenza-specific immunoglobulin A; if the mother requires antiviral treatment, oral oseltamivir is preferred. 1

• COVID-19: Direct breastfeeding with appropriate infection control measures (mask wearing, hand hygiene) is safe, as SARS-CoV-2 is unlikely to be transmitted via human milk. 5

• Most viral infections: Breast milk is not an important mode of transmission, and continuation of breastfeeding is in the best interest of both infant and mother. 3

Rare exceptions requiring temporary cessation:

• HIV, HTLV-I, and CMV in preterm infants: These are the primary viral contraindications to breastfeeding. 3

Bacterial Infections

• Maternal bacterial infections rarely transmit through breast milk and do not require cessation of breastfeeding. 3

• Mastitis: Continue breastfeeding during antibiotic treatment, as this helps resolve the condition through regular breast emptying. 4

• Temporary cessation (24 hours only) may be appropriate for: N. gonorrhoeae, H. influenzae, Group B streptococci, and staphylococci. 3

• Longer cessation may be needed for: B. burgdorferi, T. pallidum, and M. tuberculosis, with prophylactic therapy for the infant. 3

When Mother or Infant Is Hospitalized

• Hospital policies should support continued breastfeeding during maternal or infant illness, as this benefits both parties and eases nursing care. 2

• The ill mother avoids engorgement and mastitis; the infant receives antibodies to the illness, easily digested nutrition, and emotional comfort. 2

• If the mother is too ill to breastfeed directly, she should pump and feed expressed milk to maintain supply and provide continued protection to the infant. 1

Critical Pitfalls to Avoid

• Do not advise "pump and dump" or expressing and discarding milk unless there is a specific, evidence-based contraindication—this advice is inconsistent, often incorrect, and contributes to early cessation of breastfeeding. 1

• Do not assume the mother needs to stop breastfeeding when she requires anesthesia or surgery—she can resume as soon as she is alert and able to hold the baby. 1

• By the time a diagnosis is made, the infant has usually already been exposed to the pathogen, so stopping breastfeeding only deprives the infant of nutritional and immunologic benefits. 3