Pronunciation: dex-klor-fen-AIR-uh-meen MAL-ee-ate
Class: Nonselective alkylamine
- Tablets, extended-release 4 mg
- Tablets, extended-release 6 mg
- Syrup, 2 mg per 5 mL
Competitively antagonizes histamine H 1 at receptor sites.
C max approximately 7 ng/mL. T max approximately 3 h.
69% to 72% protein bound.
The t ½ is 20 to 24 h. Approximately 19% of dose is excreted in urine as parent drug and metabolites in 24 h.
Indications and Usage
Treatment of perennial and seasonal allergic rhinitis; vasomotor rhinitis; allergic conjunctivitis; mild, uncomplicated allergic skin manifestations of urticaria and angioedema; amelioration of allergic reactions to blood or plasma; dermographism; adjunctive anaphylactic therapy.
Treatment of lower respiratory tract symptoms; MAOI therapy; any component of the product or other antihistamines of similar chemical structure. Antihistamines also are contraindicated in newborn or premature infants, and breast-feeding mothers.
Dosage and AdministrationAdults and Children 12 yr of age and older
PO Tablets : 4 or 6 mg at bedtime or every 8 to 10 h.
PO Syrup : 2 mg (1 teaspoonful) every 4 to 6 h.Children 6 to 12 yr of age
PO Tablets : 4 mg/ day, preferably at bedtime.
PO Syrup : 1 mg (½ teaspoonful) every 4 to 6 h.Children 2 to 5 yr of age
PO Syrup : 0.5 mg (¼ teaspoonful) every 4 to 6 h.
- Advise patient to swallow extended-release tablets whole and not to crush, chew, or break the tablet.
- Measure and administer prescribed oral syrup dose using dosing syringe, dosing spoon, or dosing cup.
Store extended-release tablets and syrup between 36° and 86°F.
Drug InteractionsAlcohol, other sedatives
Will potentiate the sedative effects of dexchlorpheniramine.MAOIs
May cause severe hypotension.
Laboratory Test Interactions
May interfere with diagnostic test results for skin tests using allergen extracts.
Palpitations; tachycardia; extrasystoles; hypotension.
Drowsiness; headache; sedation; dizziness; vertigo; disturbed coordination; fatigue; confusion; restlessness; excitation; nervousness; tremor; irritability; insomnia; euphoria; paresthesia; hysteria; neuritis; convulsions.
Urticaria; drug rash.
Tinnitus; acute labyrinthitis; blurred vision; nasal stuffiness.
Dryness of mouth, nose, and throat; epigastric distress; anorexia; nausea; vomiting; diarrhea; constipation.
Urinary frequency; difficult urination; urinary retention; early menstruation.
Hemolytic anemia; hypoplastic anemia; thrombocytopenia; agranulocytosis.
Thickening of bronchial secretions; tightness of chest; wheezing.
Anaphylactic shock; photosensitivity; excessive perspiration; chills.
Assess for allergy symptoms (eg, rhinitis, nasal congestion, sneezing, itching, watery eyes) before and periodically throughout therapy. Monitor patient for dizziness and excessive drowsiness. If noted, hold therapy.
Category B .
Safety and efficacy not established in children younger than 6 yr of age.Syrup
Safety and efficacy not established in children younger than 2 yr of age.
More likely to have dizziness, sedation, and hypotension.
Special Risk Patients
Use with caution in patients with hypertension, heart disease, hyperthyroidism, increased IOP, diabetes mellitus, prostatic hypertrophy, bronchial asthma, narrow-angle glaucoma, stenosing peptic ulcer, pyloroduadenal obstruction, and bladder-neck obstruction.
CNS depression and stimulation (particularly in children), death, dizziness, tinnitus, ataxia, blurred vision, hypotension.
- Advise patient to take each dose without regard to meals but to take with food if stomach upset occurs.
- Advise patient using extended-release tablets to swallow tablets whole and not to crush, chew, or break the tablet.
- Advise patient or caregiver using oral syrup to administer prescribed dose 4 times daily. Advise patient or caregiver to measure and administer prescribed dose using dosing syringe, dosing spoon, or dosing cup.
- Advise patient if a dose is missed to take it as soon as possible unless it is nearing time for the next scheduled dose. If it is nearing time for next scheduled dose, advise patient to skip the missed dose and take the next dose at the regularly scheduled time. Caution patient not to double the dose to catch up.
- Advise patient if allergy symptoms are not controlled, not to increase dose of medication or frequency of use but to inform health care provider. Caution patient that larger doses or more frequent dosing does not increase effectiveness and may cause excessive drowsiness or other adverse reactions.
- Instruct patient to stop taking drug and immediately report any of these symptoms to health care provider: persistent dizziness; excessive drowsiness; severe dry mouth, nose, or throat; flushing; unexplained shortness of breath or difficulty breathing; unusual tiredness or weakness; sore throat, fever, or other signs of infection; bleeding or unusual bruising; fast or irregular heartbeat; excitability, confusion, or changes in thinking or behavior; chest tightness; difficulty with urination.
- Advise patient medication may cause drowsiness or dizziness and not to drive or perform other activities requiring mental alertness until tolerance is determined.
- Advise patient to take sips of water, suck on ice chips or sugarless hard candy, or chew sugarless gum if dry mouth occurs.
- Caution patient alcohol and other CNS depressants (eg, sedatives) will have additional sedative effects if taken with dexchlorpheniramine.
- Caution patient not to take any OTC antihistamines while taking this medication unless advised by health care provider.
- Caution patient that medication may cause sensitivity to sunlight and to avoid excessive exposure to sun or UV light (eg, tanning booths) and to wear protective clothing and use sunscreens until tolerance is determined.
- If patient is to have allergy skin testing, advise not to take medication for at least 4 days before skin testing.
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