Brom Mal Phenyl HCl Dex HBr

Beta-adrenergic blockers and MAO inhibitors may potentiate the pressor effect of phenylephrine. Concurrent use of digitalis glycosides may increase the possibility of cardiac arrhythmias. Sympathomimetics may reduce the hypotensive effects of guanethidine, mecamylamine, methyldopa, reserpine and veratrum alkaloids. Concurrent use of tricyclic antidepressants may antagonize the effects of phenylephrine. Use of other vasopressor drugs during halothane anesthia may cause serious cardiac arrhythmias.

Brom Mal/Phenyl HCl/ Dex HBr 4/7.5/15 mg/5 mL Liquid is an alcohol-free, sugar-free, dye-free, strawberry-flavored, clear liquid.
Each 5 mL (one teaspoonful) for oral administration contains:
Brompheniramine maleate........................................ 4 mg
Phenylephrine hydrochloride ................................. 7.5 mg
Dextromethorphan hydrobromide.............................15 mg

Brom Mal/Phenyl HCl/ Dex HBr 4/7.5/15 mg/5 mL Liquid also contains: glycerin, propylene glycol, sorbitol, citric acid, sodium citrate, sodium saccharin, strawberry flavor, purified water.

Brompheniramine Maleate is an antihistamine having the chemical name, 2-Pyridinepropanamine,у-(4-bromophenyl)-N, N-dimethyl-, (±)-,(Z)-2-butenedioate (1:1), with the following structure:

Phenylephrine hydrochloride is an orally effective nasal decongestant. Chemically it is (–)-m-Hydroxy-α-[(methylamino)methyl]benzyl alcohol hydrochloride with the following chemical structure:

Dextromethorphan hydrobromide is a salt of the methyl ether of the dextrorotatory isomer of levorphanol, a narcotic analgesic. Chemically, it is 3-methoxy-17-9α, 13α, 14α-morphinan hydrobromide monohydrate and has the following structural formula:

12.1 Mechanism of Action
Brompheniramine maleate
Alkylamine-type antihistamines such as brompheniramine maleate are among the most potent H1 blockers and are generally effective in relatively low doses. Although brompheniramine is not as prone as other types of antihistamines to cause drowsiness, a significant proportion of patients do experience this effect. CNS stimulation is more common with alkylamines.

Phenylephrine HCl
Phenylephrine hydrochloride is a sympathomimetic amine which acts predominantly by a direct action on alpha (α) adrenergic receptors. In therapeutic doses, the drug has no significant stimulant effect on the beta (β) adrenergic receptors of the heart. Clinically, phenylephrine shrinks swollen mucous membranes, reduces tissue hyperemia, edema, and nasal congestion; and increases nasal airway patency. In therapeutic doses the drug causes little, if any, central nervous system (CNS) stimulation.

Dextromethorphan hydrobromide
Dextromethorphan hydrobromide acts centrally to elevate the threshold for coughing. It has no analgesic or addictive properties. The onset of antitussive action occurs in 15 to 30 minutes after administration and is of long duration.