- Tablets: 4 mg
- Syrup: 2 mg/5mL, 0.4 mg/mL
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.
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.
CNS: drowsy, poor coordination, tonic/clonic seizures
GI: dry mouth, diarrhea, constipation
GU: urine retention
Other: maycause thick bronchial secretions
0.2 mg/lb, PO, BID, for allergy/respiratory symptoms 12
0.6 mg/kg, PO, q24hr 42
- 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.