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Peds Calc

Pediatric Reference

Chlorpheniramine Side EffectsComprehensive Pediatric Safety Guide

Sedation, dry mouth, and slowed reaction time are common. Rarely, paradoxical agitation or hallucinations can occur, especially with higher doses or in younger children.

3 Categories
5 Clinical Sources
Evidence-Based
Back to Chlorpheniramine Overview

Essential Information

1

Plan homework, driving, and sports around possible drowsiness

2

Encourage fluids, saline spray, and humidifier use to offset drying

3

Call immediately for hallucinations, severe agitation, trouble urinating, or chest pounding

Clinical Overview

Monitor closely during the first days of therapy, adjust timing to bedtime, and stop immediately for severe behavioral or cardiovascular symptoms.

Side Effect Categories

3 Systems

Central nervous system

2 documented effects

Total Sources: 2

Drowsiness / slowed reaction time

Incidence: Very common
Onset: Not specified
mild to moderate
1 sources
Duration

Not specified

Management

Move doses to evening/bedtime; avoid other sedatives; monitor school performance

Monitoring Guidelines

Monitor for symptom escalation or new adverse effects.

1 clinical sources• PubMed • Clinical Guidelines • FDA

Paradoxical excitation, nervousness, hallucinations

Incidence: Uncommon
Onset: Not specified
severe
1 sources
Duration

Not specified

Management

Stop the medicine and seek urgent care

Monitoring Guidelines

Monitor for symptom escalation or new adverse effects.

1 clinical sources• PubMed • Clinical Guidelines • FDA

Anticholinergic

2 documented effects

Total Sources: 2

Dry mouth / thick secretions

Incidence: Common
Onset: Not specified
mild
1 sources
Duration

Not specified

Management

Offer water, use humidifier, encourage saline spray

Monitoring Guidelines

Monitor for symptom escalation or new adverse effects.

1 clinical sources• PubMed • Clinical Guidelines • FDA

Urinary retention / blurred vision

Incidence: Rare
Onset: Not specified
moderate to severe
1 sources
Duration

Not specified

Management

Stop medication and evaluate, especially in adolescents with bladder issues

Monitoring Guidelines

Monitor for symptom escalation or new adverse effects.

1 clinical sources• PubMed • Clinical Guidelines • FDA

Gastrointestinal

1 documented effect

Total Sources: 1

Nausea

Incidence: Common
Onset: Not specified
mild
1 sources
Duration

Not specified

Management

Give with light snack; monitor hydration

Monitoring Guidelines

Monitor for symptom escalation or new adverse effects.

1 clinical sources• PubMed • Clinical Guidelines • FDA

Parent Communication Guide

Age-Appropriate Explanations

Infants (0-12 months)

For babies taking Chlorpheniramine, watch for signs of side effects. This medication is generally well-tolerated in infants when used as directed.

Toddlers (1-3 years)

This medicine might make your child very sleepy or cranky.

Children (4-12 years)

It can make you tired; tell us if you feel dizzy or your heart is racing.

Adolescents (13+ years)

Don’t drive or play sports until you know how sleepy it makes you; call if you feel agitated or have vision changes.

Common Parent Concerns

Q: Child can’t stay awake at school

A: Use bedtime-only dosing or stop the medicine and switch to a non-sedating antihistamine.

When to validate: Contact clinician if daytime functioning is impaired.

Q: Child feels jittery or has a fast heartbeat

A: Stop the medicine immediately and seek medical advice—this can be a sign to avoid the drug.

When to validate: Urgent evaluation if symptoms persist or worsen.

Clinical Decision Support

Severity Assessment Framework

Guide whether to continue, adjust, or stop therapy based on sedation and behavioral effects.

Mild
Indicators: Predictable drowsiness, Dry mouth
Action: Continue with bedtime dosing and supportive care
Moderate
Indicators: Daytime impairment, Mild agitation
Action: Consider dose reduction or discontinuation
Severe
Indicators: Hallucinations, Seizure, Severe tachycardia
Action: Discontinue immediately and seek urgent care

Treatment Decision Guidelines

Immediate Discontinuation

  • Anaphylaxis
  • Severe neuropsychiatric symptoms
  • Palpitations accompanied by dizziness or chest pain

Consider Alternatives

  • Persistent daytime sedation
  • Recurrent paradoxical excitation

Dose Modification

  • Mild drowsiness only

Clinical References

Frequently Asked Questions

Parent and clinician concerns about Chlorpheniramine