Chlorpheniramine Maleate

Pronunciation: (klor-fen-AIR-uh-meen MAL-ee-ate)\

Class: Alkylamine, nonselective

Trade Names:

Aller-Chlor
- Tablets 4 mg
- Syrup 2 mg per 5 mL

Trade Names:

Allergy
- Tablets 4 mg

Trade Names:
Allergy Relief
- Tablets 4 mg

Trade Names:

Chlor-Trimeton
- Tablets 4 mg

Trade Names:

Chlor-Trimeton Allergy 8 Hour
- Tablets, extended-release 8 mg

Trade Names:

Chlor-Trimeton Allergy 12 Hour
- Tablets, extended-release 12 mg

Trade Names:

Chlorpheniramine Maleate
- Capsules, sustained-release 8 mg
- Capsules, sustained-release 12 mg

Trade Names:

Chlorpheniramine Maleate
- Tablets 4 mg
Chlor-Tripolon (Canada)

Pharmacology

Competitively antagonizes histamine at H 1 receptor sites.

Pharmacokinetics

Absorption

Readily absorbed.

Distribution

72% protein bound.

Metabolism

Metabolized predominantly in the liver, but also in the lung and kidneys.

Elimination

Renally eliminated, mostly as metabolites within 24 h.

Indications and Usage

Temporary relief of sneezing, itchy, watery eyes, itchy nose or throat, and runny nose caused by hay fever (allergic rhinitis), or other respiratory allergies.

Contraindications

Hypersensitivity to antihistamines; narrow-angle glaucoma; stenosing peptic ulcer; symptomatic prostatic hypertrophy; asthmatic attack; bladder neck obstruction; pyloroduodenal obstruction; MAO therapy; use in newborn or premature infants and in breast-feeding mothers.

Dosage and Administration

Immediate-release tablet or syrup

Adults and children 12 yr of age and older

PO 4 mg every 4 to 6 h (max, 24 mg/day).

Children 6 to younger than 12 yr of age

PO 2 mg every 4 to 6 h (max, 12 mg/day).

Children younger than 5 yr of age

PO As recommended by health care provider.

Extended-release tablets

Adults and children 12 yr of age and older

PO 8 mg every 8 to 12 h or 12 mg every 12 h (max, 24 mg/day).

Extended-release capsules

Adults and children 12 yr of age and older

PO 8 or 12 mg in the morning and evening (max, 24 mg/day).

General Advice

* Administer without regard to meals. Administer with food if GI upset occurs.
* Measure and administer prescribed dose of oral syrup using dosing syringe, dosing spoon, or dosing cup.
* Advise patient receiving extended-release tablets or sustained-release capsules to swallow tablets or capsules whole and not to crush, chew, break, or open.

Storage/Stability

Store all dose forms at controlled room temperature (59° to 86°F).

Drug Interactions


Lopinavir plasma concentration of chlorphenamine (chlorpheniramine) possibly increased by lopinavir In combination with ritonavir as Kaletra® (ritonavir is present to inhibit lopinavir metabolism and increase plasma-lopinavir concentration)—see also Ritonavir
Chlorphenamine (chlorpheniramine) belongs to Antihistamines, Sedating but Antihistamines, Sedating has no interactions information.
Chlorphenamine (chlorpheniramine) belongs to Antihistamines and will have the following interactions:
Sedative interactions apply to a lesser extent to the non-sedating antihistamines. Interactions do not generally apply to antihistamines used for topical action (including inhalation)

Alcohol increased sedative effect when antihistamines given with alcohol (possibly less effect with non-sedating antihistamines)
Antidepressants, Tricyclic increased antimuscarinic and sedative effects when antihistamines given with tricyclics
Antidepressants, Tricyclic (related) possible increased antimuscarinic and sedative effects when antihistamines given with tricyclic-related antidepressants
Antimuscarinics increased risk of antimuscarinic side-effects when antihistamines given with antimuscarinics Many drugs have antimuscarinic effects; concomitant use of two or more such drugs can increase side-effects such as dry mouth, urine retention, and constipation; concomitant use can also lead to confusion in the elderly. Interactions do not generally apply to antimuscarinics used by inhalation
Anxiolytics and Hypnotics increased sedative effect when antihistamines given with anxiolytics and hypnotics
Betahistine antihistamines theoretically antagonise effect of betahistine
MAOIs increased antimuscarinic and sedative effects when antihistamines given with MAOIs For interactions of reversible MAO-A inhibitors (RIMAs) see Moclobemide, and for interactions of MAO-B inhibitors see Rasagiline and Selegiline; the antibacterial Linezolid is a reversible, non-selective MAO inhibitor


Adverse Reactions

Cardiovascular

Bradycardia; extrasystoles; orthostatic hypotension; palpitations; reflex tachycardia; tachycardia.

CNS

Confusion; convulsions; disturbed coordination; dizziness; drowsiness; euphoria; excitation; faintness; fatigue; headache; hysteria; insomnia; irritability; nervousness; neuritis; paresthesias; restlessness; sedation; tremor; vertigo.

EENT

Acute labyrinthitis; blurred vision; diplopia; dry nose and throat; nasal stuffiness; sore throat; tinnitus.

GI

Anorexia; constipation; diarrhea; dry mouth; epigastric distress; nausea; vomiting.

Genitourinary

Difficult urination; dysuria; early menses; urinary frequency or retention.

Hematologic

Agranulocytosis; hemolytic anemia; thrombocytopenia.

Metabolic

Increased appetite; weight gain.

Respiratory

Chest tightness; respiratory depression; thickening of bronchial secretions; wheezing.

Miscellaneous

Chills; excessive perspiration; hypersensitivity reactions; photosensitivity.

Precautions

Monitor

Allergy symptoms

Assess allergy symptoms (eg, cough, rhinitis, nasal congestion, sneezing, watery eyes, or itching nose, throat, or eyes) before starting therapy and periodically during therapy. Notify health care provider if symptoms are not improving or are getting worse.

Dizziness/Drowsiness

Monitor patient for dizziness and excessive drowsiness. If noted, hold therapy and notify health care provider.

Review therapy

Ensure therapy periodically is reviewed to determine if it needs to be continued without change or if a dose change (eg, increase, decrease, discontinuation) is indicated.

Pregnancy

Category C . Do not use during third trimester.

Lactation

Contraindicated in breast-feeding mothers.

Children

Overdosage may cause hallucinations, convulsions, and death. Antihistamines may diminish mental alertness. In young children, they may produce paradoxical excitation. Contraindicated in newborn or premature infants. Sustained-release form not recommended in children younger than 12 yr of age.

Elderly

Use with caution, usually starting at the low end of the dosage range because of the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant diseases or other drug therapy.

Hypersensitivity

May occur. Have epinephrine 1:1,000 immediately available.

Hepatic Function

Use drug with caution in patients with cirrhosis or other liver disease.

Special Risk Patients

Use drug with caution in patients with predisposition to urinary retention, history of bronchial asthma, increased IOP, hyperthyroidism, CV disease, or hypertension. Avoid in patients with sleep apnea.

RESP disease

Generally not recommended to treat lower respiratory tract symptoms, including asthma.

Overdosage

Symptoms

CNS depression (including sedation, apnea, CV collapse), CNS stimulation (including insomnia, hallucination, tremors, convulsions), tinnitus, blurred vision, dizziness, ataxia, hypotension. Stimulation and atropine-like signs and symptoms (including dry mouth, fixed dilated pupils, flushing, hyperthermia, GI symptoms) are more likely in children.

Patient Information

* Caution patient using OTC chlorpheniramine that each product has specific dosing instructions and to read package label before using and not to exceed dose or frequency of administration instructions.
* Advise patient to take each dose without regard to meals, but to take with food if stomach upset occurs.
* Advise patient or caregiver using oral syrup to measure and administer prescribed dose using dosing syringe, dosing spoon, or dosing cup.
* Advise patient that 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 that if allergy symptoms are not controlled, not to increase the 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 efficacy 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 chlorpheniramine.
* Caution patient not to take any other 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 the 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 patient not to take the medication for at least 4 days before the skin testing.