CPM (Chlorpheniramine Maleate) Drops in Healthy Infants

What is CPM?

Why it should NOT be used in infants

1. No proven benefit

• Cold-related nasal congestion and rhinorrhea in infants are primarily caused by viral inflammation, not histamine release — so antihistamines have no meaningful mechanism of benefit.
• Antihistamines do not shorten the duration of upper respiratory illness, reduce rhinorrhea, or decrease complications like otitis media in young children.
• There is no evidence that antihistamines or combined antihistamine-decongestant preparations benefit young children with colds. (Swanson's Family Medicine Review)

2. Significant safety risks

• Young children (especially infants) are highly sensitive to first-generation antihistamines like chlorpheniramine on a mg/kg basis.
• Known adverse effects in infants include:
  • CNS paradoxical excitation (irritability, insomnia, agitation) — opposite of sedation
  • Seizures — reported when doses intended for older children are given to infants
  • Respiratory depression at higher doses
  • Overstimulation or sedation

3. Regulatory position

• In 2008, the FDA required labeling changes for over-the-counter (OTC) cough and cold medications due to safety concerns, including fatalities, in children.
• The recommendation was that these products should not be used in children under 2 years, and with caution in children under 6 years.
• A surveillance study (Halmo et al., Pediatrics 2021 [PMID: 34607934]) found that 60% of pediatric fatalities associated with cough-and-cold medications occurred in children under 2 years old. Chlorpheniramine was among the implicated drugs.

What to do instead for a healthy infant with cold symptoms

• Nasal saline drops with gentle bulb suctioning
• Humidified air (cool-mist humidifier)
• Adequate hydration
• Reassurance — most viral URIs in healthy infants are self-limiting

Bottom line