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Sildec Syrup

Generic name: brompheniramine maleate and pseudoephedrine hydrochloride
Dosage form: syrup

Medically reviewed by Last updated on April 21, 2021.

Disclaimer: This drug has not been found by FDA to be safe and effective, and this labeling has not been approved by FDA. For further information about unapproved drugs, click here.

Sildec Syrup Description

Antihistamine/Decongestant for oral use.

For adults and pediatric patients (2 years and older)
Brompheniramine Maleate/Pseudoephedrine Hydrochloride Syrup

Each teaspoonful (5 mL) contains brompheniramine maleate, 4 mg; pseudoephedrine hydrochloride, 45 mg.

Inactive ingredients: citric acid, FD&C Red No. 40, glycerin, flavor, purified water, saccharin sodium, sodium benzoate, sodium citrate,

Brompheniramine maleate (2-Pyridnepropanamine, y-(4-bromophenyl)- N, N-dimethyl-, (±)-, (Z)-2-butenedioate).

Pseudoephedrine hydrochloride (Benzenemethanol, α-[1-(methylamino)ethyl]-,[S-(R*,R*)]-, hydrochloride) is the hydrochloride of pseudoephedrine, a naturally occurring dextrorotatory stereoisomer of ephedrine.

Sildec Syrup - Clinical Pharmacology

Antihistaminic and decongestant actions.

Brompheniramine maleate possesses H1 antihistaminic activity and mild anticholinergic and sedative effects. Peak plasma concentration is reached in 5 hours. Urinary excretion is the major route of elimination. The liver is assumed to be the major site of metabolic transformation.

Pseudoephedrine hydrochloride is an oral sympathomimetic amine that acts as a decongestant to respiratory tract mucous membranes. While its vasoconstrictor action is similar to that of ephedrine, pseudoephedrine has less pressor effect in normotensive adults. Serum half-life for pseudoephedrine is 6 to 8 hours. Acidic urine is associated with faster elimination of the drug. About one-half of the administered dose is excreted in the urine.

Indications and Usage for Sildec Syrup

Symptomatic relief of seasonal and perennial allergic rhinitis and vasomotor rhinitis. This product is an immediate-release dosage form allowing titration of dose up to four times a day.


Patients with hypersensitivity or idiosyncrasy to any of its ingredients. Sympathomimetic amines are contraindicated in patients with severe hypertension, severe coronary artery disease and patients on monoamine oxidase (MAO) inhibitor therapy. Antihistamines are contraindicated in patients with narrow-angle glaucoma, urinary retention, peptic ulcer, and during an asthma attack.


Sympathomimetic amines should be used judiciously and sparingly in patients with hypertension, diabetes, ischemic heart disease, hyperthyroidism, increased intraocular pressure, or prostatic hypertrophy. (See CONTRAINDICATIONS.) Sympathomimetic amines may produce CNS stimulation with convulsions or cardiovascular collapse with accompanying hypotension. The elderly (60 years and older) are more likely to exhibit adverse reactions. Antihistamines may cause excitability, especially in children. At doses higher than the recommended dose, nervousness, dizziness, or sleeplessness may occur. Do not exceed recommended doses.


Use with caution in patients with hypertension, heart disease, asthma, hyperthyroidism, increased intraocular pressure, diabetes mellitus, and prostatic hypertrophy.

Information for Patients: Avoid alcohol and other CNS depressants while taking this product. Patients sensitive to antihistamines may experience moderate to severe drowsiness. Patients sensitive to sympathomimetic amines may note CNS stimulation.

Drug Interactions: Antihistamines may enhance the effects of tricyclic antidepressants, barbiturates, alcohol, and other CNS depressants. MAO inhibitors prolong and intensify the anticholinergic effects of antihistamines. Sympathomimetic amines may reduce the antihypertensive effects of reserpine, veratrum alkaloids, methyldopa, and mecamylamine. Effects of sympathomimetics are increased with MAO inhibitors and beta-adrenergic blockers.

Pregnancy Category C: Animal reproduction studies have not been conducted with this product. It is not known whether this product can cause fetal harm when administered to a pregnant woman or affect reproduction capacity. Give to pregnant women only if clearly needed.

Nursing Mothers: It is not known if the drugs in this product are excreted in human milk. Since many drugs are excreted into human milk and because of the potential for serious side effects in the nursing infant, this product should only be given to nursing mothers if clearly needed.

Pediatric Use: Safety and effectiveness of this product in pediatric patients below the age of two years have not been established.

Adverse Reactions

Antihistamines: Sedation, dizziness, diplopia, vomiting, diarrhea, dry mouth, headache, nervousness, nausea, anorexia, heartburn, weakness, polyuria and dysuria and, rarely, excitability in children. Urinary retention may occur in patients with prostatic hypertrophy.

Sympathomimetic amines: Convulsions, CNS stimulation, cardiac arrhythmia, respiratory difficulties, increased heart rate or blood pressure, hallucinations, tremors, nervousness, insomnia, pallor and dysuria.


The signs, symptoms, and treatment described below are those for H1 antihistamines, and pseudoephedrine overdose.

Symptoms: Should antihistamine effects predominate central action constitutes the greatest danger. In the small child, predominate symptoms are excitation, hallucination, ataxia, incoordination, tremors, flushed face and fever. Convulsions, fixed and dilated pupils, coma, and death may occur in severe cases. In the adult, fever and flushing are uncommon; excitement leading to convulsions and postictal depression is often preceded by drowsiness and coma. Respiration is usually not seriously depressed; blood pressure is usually stable.

Should sympathomimetic symptoms predominate, central effects include restlessness, dizziness, tremor, hyperactive reflexes, talkativeness, irritability, and insomnia. Cardiovascular and renal effects include difficulty in micturition, headache, flushing, palpitation, cardiac arrhythmia, hypertension with subsequent hypotension and circulatory collapse. Gastrointestinal effects include dry mouth, metallic taste, anorexia, nausea, vomiting, diarrhea, and abdominal cramps.

Treatment: a) Evacuate stomach as condition warrants. Activated charcoal may be useful. b) Maintain a non-stimulating environment. c) Monitor cardiovascular status. d) Do not give stimulants. e) Reduce fever with sponging. f) Use sedatives or anti-convulsants to control CNS excitation and convulsions. g) Physostigmine may reverse anticholinergic symptoms. h) Ammonium chloride may acidify the urine to increase urinary excretion of pseudoephedrine. i) Further care is symptomatic and supportive.

Sildec Syrup Dosage and Administration

2-6 years
1/2 teaspoonful (2.5 mL)
Adults and pediatric patients 6 years and over
1 teaspoonful (5 mL)
*In mild cases or in particularly sensitive patients, less frequent or reduced doses may be adequate.

How is Sildec Syrup Supplied

Brompheniramine Maleate/Pseudoephedrine Hydrochloride Syrup, raspberry flavored, in 4 fl oz and 16 fl oz bottles.
Dispense in a tight, light-resistant container as defined in USP.
Store between 46°-86°F (8°-30°C). Avoid exposure to heat. Keep tightly closed.

Rx only.

Manufactured by:
Silarx Pharmaceuticals, Inc.
Spring Valley, NY 10977

Sildec Syrup
Sildec Syrup syrup
Product Information
Product Type HUMAN PRESCRIPTION DRUG LABEL Item Code (Source) NDC:54838-534
Route of Administration ORAL DEA Schedule
Active Ingredient/Active Moiety
Ingredient Name Basis of Strength Strength
Brompheniramine Maleate (Brompheniramine) Brompheniramine Maleate 4 mg in 5 mL
Pseudoephedrine Hydrochloride (Pseudoephedrine) Pseudoephedrine Hydrochloride 45 mg in 5 mL
Inactive Ingredients
Ingredient Name Strength
anhydrous citric acid
FD&C Red No. 40
saccharin sodium
sodium benzoate
sodium citrate
Product Characteristics
Color Score
Shape Size
Flavor RASPBERRY Imprint Code
# Item Code Package Description
1 NDC:54838-534-80 473 mL in 1 BOTTLE, PLASTIC
Marketing Information
Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date
unapproved other 03/01/2001
Labeler - Silarx Pharmaceuticals, Inc (161630033)
Silarx Pharmaceuticals, Inc

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