Which medications for upper respiratory tract infection are contraindicated in a breastfeeding mother?

Medications for URTI Contraindicated in Breastfeeding

Very few medications for upper respiratory tract infections are absolutely contraindicated during breastfeeding, and most commonly used treatments are safe. The key is understanding which specific agents to avoid and which are preferred alternatives.

Absolute Contraindications

There are no absolute contraindications among standard URTI medications for breastfeeding mothers 1, 2. The classic absolute contraindications to breastfeeding involve conditions unrelated to URTI treatment: HIV infection, untreated brucellosis, Ebola virus disease, anticancer agents, and radioactive drugs 1, 2.

Medications to Avoid or Use with Extreme Caution

Decongestants

• Oral decongestants (pseudoephedrine, phenylephrine) should be avoided as they may reduce milk production and can cause irritability and insomnia in infants 1, 3.
• Pseudoephedrine specifically has been shown to decrease milk supply 3.
• If a decongestant is absolutely necessary, pseudoephedrine transfers in low levels to breast milk and is considered "compatible" by some sources, but the risk of reduced milk production remains 3.

Antihistamines

• First-generation antihistamines should be avoided due to their sedative and anticholinergic properties, which can cause drowsiness or paradoxical CNS stimulation in infants 1, 3.
• Examples include diphenhydramine, chlorpheniramine, and promethazine 3.
• Preferred alternatives: Triprolidine and loratadine are considered compatible with breastfeeding as they transfer in low levels to breast milk 3.

Aspirin

• Aspirin at doses >100 mg/day should be avoided as it has been associated with significant adverse effects in nursing infants, including metabolic acidosis and Reye's syndrome risk 3, 4.
• Low-dose aspirin (≤100 mg/day) is considered compatible 4.

Combination Products

• Avoid multi-ingredient cough and cold preparations that contain unnecessary combinations of antihistamines, decongestants, and analgesics 3.
• Many liquid formulations contain alcohol, which should be minimized 3.

Safe Alternatives for URTI Symptoms

For Nasal Congestion

• Saline nasal rinses are the safest first-line treatment and are explicitly recommended during breastfeeding 1.
• Topical corticosteroid nasal sprays are safe and effective 1.

For Cough

• Codeine is considered compatible with breastfeeding for short-term use as a cough suppressant 3.
• Use at the lowest effective dose and for the shortest duration 3.

For Pain/Fever

• Acetaminophen (paracetamol) is the preferred analgesic and is fully compatible with breastfeeding 3, 4.
• Ibuprofen and other NSAIDs are safe for short-term use at standard doses 3, 4.

For Bacterial Infections (if indicated)

• Amoxicillin and amoxicillin/clavulanate are first-line choices and are classified as "compatible" with breastfeeding 1, 5, 4.
• Cephalosporins (e.g., cephalexin) are safe alternatives 1, 5, 4.
• Azithromycin is "probably safe" but should ideally be avoided in the first 13 days postpartum due to a very low risk of infantile hypertrophic pyloric stenosis 5, 6.
• Fluoroquinolones should not be used as first-line treatment but are not absolutely contraindicated; if necessary, ciprofloxacin is preferred 5, 4.

Clinical Decision Algorithm

1. Start with non-pharmacologic measures: Saline rinses, hydration, humidification 1.
2. For symptom relief:
   • Pain/fever → Acetaminophen or ibuprofen 3, 4
   • Cough → Codeine (short-term only) 3
   • Nasal congestion → Topical corticosteroid spray, avoid oral decongestants 1, 3
   • Allergic symptoms → Loratadine or triprolidine, avoid first-generation antihistamines 3
3. For bacterial infection: Amoxicillin or amoxicillin/clavulanate first-line 5, 4.
4. Timing strategy: Take medications immediately after breastfeeding to minimize infant exposure 3.

Common Pitfalls to Avoid

• Do not recommend "just stop breastfeeding" – the vast majority of URTI medications are compatible with continued nursing 2, 4.
• Do not prescribe combination cold products when single-agent therapy targeting specific symptoms is safer 3.
• Do not use oral decongestants without warning about milk supply reduction 1, 3.
• Monitor infants for adverse effects: Watch for irritability, drowsiness, or feeding changes when mother takes any medication 3.
• Remember that antibiotics in breast milk may alter infant gut flora and potentially cause mild diarrhea, but this rarely requires treatment discontinuation 5, 4.