(chlorpheniramine)
Brands
Chlor-Trimeton, Aller-Chlor
Availability
- Tablets: 4 mg
- Syrup: 2 mg/5mL, 0.4 mg/mL
Pharmacology
An alkylamine derivative, this drug is among the most potent of antihistamines but unlike the ethanolamine derivatives is only minimally sedative. Like other antihistaminics it blocks histamine at the receptor site.
It is well absorbed orally and distributed in high levels to spleen, lungs, and brain. It is able to cross the placental barrier.
The drug is metabolized in the liver and excreted as metabolites in urine and breast milk.
Indications
Used where allergy symptoms, or nasal congestion are present.
Drug Interactions or Contraindications:
- Use cautiously with central nervous system depressants as it can increase sedative effect.
- Do not use for acute asthmatic attacks.
- Not recommended to be given to pregnant or lactating rats.
Adverse Reactions
CNS: drowsy, poor coordination, tonic/clonic seizures
CV: palpitations
GI: dry mouth, diarrhea, constipation
GU: urine retention
Other: maycause thick bronchial secretions
Dosage Recommendations
0.2 mg/lb, PO, BID, for allergy/respiratory symptoms 12
or
0.6 mg/kg, PO, q24hr 42
Considerations
- Can be purchased over the counter.
- Give lots of fluids to decrease bronchial secretion viscosity.
- Avoid milk products.
- Give with food to avoid GI reactions.
- Store drug at room temperature.
