General

Because of its antihistamine component, brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup should be used with caution in patients with a history of bronchial asthma, narrow angle glaucoma, gastrointestinal obstruction, or urinary bladder neck obstruction. Because of its sympathomimetic component, brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup should be used with caution in patients with diabetes, hypertension, heart disease, or thyroid disease.

Information for Patients

Patients should be warned about engaging in activities requiring mental alertness, such as driving a car or operating dangerous machinery.

Drug Interactions

Monoamine oxidase (MAO) inhibitors

Hyperpyrexia, hypotension, and death have been reported coincident with the coadministration of MAO inhibitors and products containing dextromethorphan. In addition, MAO inhibitors prolong and intensify the anticholinergic (drying) effects of antihistamines and may enhance the effect of pseudoephedrine. Concomitant administration of brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup and MAO inhibitors should be avoided (see CONTRAINDICATIONS).

Central nervous system (CNS) depressants

Antihistamines have additive effects with alcohol and other CNS depressants (hypnotics, sedatives, tranquilizers, antianxiety agents, etc.).

Antihypertensive drugs

Sympathomimetic may reduce the effects of antihypertensive drugs.

Carcinogenesis, Mutagenesis, Impairment of Fertility

Animal studies of brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup to assess the carcinogenic and mutagenic potential or the effect on fertility have not been performed.

Pregnancy

Teratogenic Effects

Pregnancy Category C

Animal reproduction studies have not been conducted with brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup. It is also not known whether brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. It should be given to a pregnant woman only if clearly needed.

Reproduction studies of brompheniramine maleate (a component of brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup) in rats and mice at doses up to 16 times the maximum human doses have revealed no evidence of impaired fertility or harm to the fetus.

Nursing Mothers

Because of the higher risk of intolerance of antihistamines in small infants generally, and in newborns and prematures in particular, brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup is contraindicated in nursing mothers.

Pediatric Use

Safety and effectiveness in pediatric patients below the age of 6 months have not been established (see DOSAGE AND ADMINISTRATION).

Geriatric Use

Clinical studies of brompheniramine maleate, pseudoephedrine hydrochloride and dextromethorphan hydrobromide syrup did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. However, antihistamines are more likely to cause dizziness, sedation, and hypotension in elderly patients. The elderly are also more likely to experience adverse reactions to sympathomimetics.

In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

Signs and Symptoms

Central nervous system effects from overdosage of brompheniramine may vary from depression to stimulation, especially in children. Anticholinergic effects may be noted. Toxic doses of pseudoephedrine may result in CNS stimulation, tachycardia, hypertension, and cardiac arrhythmias; signs of CNS depression may occasionally be seen. Dextromethorphan in toxic doses will cause drowsiness, ataxia, nystagmus, opisthotonos, and convulsive seizures.

Toxic Doses

Data suggest that individuals may respond in an unexpected manner to apparently small amounts of a particular drug. A 2½-year-old child survived the ingestion of 21 mg/kg of dextromethorphan exhibiting only ataxia, drowsiness, and fever, but seizures have been reported in 2 children following the ingestion of 13 to 17 mg/kg. Another 2½-year-old child survived a dose of 300 to 900 mg of brompheniramine. The toxic dose of pseudoephedrine should be less than that of ephedrine, which is estimated to be 50 mg/kg.

Treatment

Induce emesis if patient is alert and is seen prior to 6 hours following ingestion. Precautions against aspiration must be taken, especially in infants and small children. Gastric lavage may be carried out, although in some instances tracheostomy may be necessary prior to lavage. Naloxone hydrochloride 0.005 mg/kg intravenously may be of value in reversing the CNS depression that may occur from an overdose of dextromethorphan. CNS stimulants may counter CNS depression. Should CNS hyperactivity or convulsive seizures occur, intravenous short-acting barbiturates may be indicated. Hypertensive responses and/or tachycardia should be treated appropriately. Oxygen, intravenous fluids, and other supportive measures should be employed as indicated.