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Sildec PE Syrup

Generic name: chlorpheniramine maleate and phenylephrine hydrochloride
Dosage form: syrup
Drug class: Upper respiratory combinations

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 PE Syrup Description

CPM/PE Syrup is a sugar-free, alcohol-free, raspberry flavored syrup for oral administration for adults and pediatric patients 2 years and older.

Each teaspoonful (5 mL) contains:
Chlorpheniramine maleate ………… 4.0 mg
Phenylephrine hydrochloride ……… 12.5 mg

Inactive ingredients: Citric acid, D & C Red No. 33, flavor, glycerin, purified water, sodium benzoate, sodium citrate, sodium saccharin, and sorbitol.

Chlorpheniramine maleate is an antihistamine with the chemical name: 2-Pyridinepropanamine, y-(4-chlorophenyl)-N, N-dimethyl-,(Z)-2-butenedioate (1:1). Its chemical structure is as follows:

Phenylephrine hydrochloride is a mydriatic and a decongestant with the chemical name: (-)-m-Hydroxy-α-[(methylamino)methyl]benzyl alcohol hydrochloride. Its chemical structure is as follows:

Sildec PE Syrup - Clinical Pharmacology

Antihistaminic and decongestant actions.

Chlorpheniramine 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.

Phenylephrine 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, phenylephrine has less pressor effect in normotensive adults. Serum half-life for phenylephrine 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 PE Syrup

Chlorpheniramine/Phenylephrine Syrup (CPM/PE Syrup)
Symptomatic relief of seasonal and perennial allergic rhinitis and vasomotor rhinitis. CPM/PE Syrup is an immediate dosage form allowing titration of dose 4-6 times per 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.


Do not exceed recommended dosage.

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.


General: 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 notice mild CNS stimulation. Antihistamines may impair mental and physical abilities required for the performance of potentially hazardous tasks such as driving a vehicle or operating machinery. Patients should be warned accordingly.

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 mecamylamines. Effects of sympathomimetics are increased with MAO inhibitors and beta-adrenergic blockers.

Use in Pregnancy: Pregnancy Category C. Animal reproduction studies have not been conducted with CPM/PE Syrup. It is not known whether these products can cause fetal harm when administered to a pregnant woman or affect reproduction capacity. Give to a pregnant woman only if clearly needed.

Nursing Mothers: It is not known whether the drugs in CPM/PE Syrup are excreted in human milk. Since many drugs are excreted in human milk and because of the potential for serious side effects in nursing infants, a decision should be made whether to discontinue nursing or discontinue the use of these products, taking into account the importance of the drugs to the mother.

Adverse Reactions

Antihistamines may cause 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 may cause convulsions, CNS stimulation, cardiac arrhythmia, respiratory difficulties, increased heart rate or blood pressure, hallucinations, tremors, nervousness, insomnia, pallor and dysuria.


No information is available as to specific results of an overdose of this product. The signs, symptoms and treatment described below are those of H1 antihistamine and ephedrine overdose.

Symptoms: Should antihistamine effects predominate, central action constitutes the greatest danger. In the small child, predominant 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 nonstimulating environment. (c) Monitor cardiovascular status. (d) Do not give stimulants. (e) Reduce fever with cool sponging. (f) Use sedatives or anticonvulsants to control CNS excitation and convulsions. (g) Physostigmine may reverse anticholinergic symptoms. (h) Ammonium chloride may acidify the urine to increase urinary excretion of phenylephrine. (i) Further care is symptomatic and supportive.

Sildec PE Syrup Dosage and Administration

Adults and Children 12 years of age and older: 1 teaspoonful (5 mL) every 4 to 6 hours, not to exceed 6 teaspoonfuls in 24 hours. Children 6 to under 12 years of age: 1/2 teaspoonful (2.5 mL) every 4 to 6 hours, not to exceed 3 teaspoonfuls in 24 hours. Children 2 to under 6 years of age: 1/4 teaspoonful(1.25) every 4 to 6 hours, not to exceed 1.5 teaspoonfuls in 24 hours. Not recommended for use in children under 2 years of age.

In mild cases or in particularly sensitive patients, less frequent or reduced doses may be appropriate and adequate.

How is Sildec PE Syrup Supplied

CPM/PE Syrup is sugar-free, alcohol-free, raspberry flavored syrup available in bottles of 16 fluid ounce (473 mL) and 4 oz (118 mL).

Dispense in a tight, light-resistant container as defined in USP with a child resistant closure.


Store at Controlled Room Temperature between 20°-25°C (68°-77°F); excursions permitted to 15°-30°C (59°-86°F) [See USP Controlled Room Temperature]. Avoid exposure to heat. Keep tightly closed.

KEEP THIS AND ALL DRUGS OUT OF THE REACH OF CHILDREN. In case of accidental overdose, seek professional assistance or contact a Poison Control Center immediately.

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

Sildec PE Syrup
Sildec PE Syrup syrup
Product Information
Product Type HUMAN PRESCRIPTION DRUG LABEL Item Code (Source) NDC:54838-542
Route of Administration ORAL DEA Schedule
Active Ingredient/Active Moiety
Ingredient Name Basis of Strength Strength
Chlorpheniramine maleate (Chlorpheniramine) Chlorpheniramine maleate 4 mg in 5 mL
Phenylephrine hydrochloride (Phenylephrine) Phenylephrine hydrochloride 12.5 mg in 5 mL
Inactive Ingredients
Ingredient Name Strength
anhydrous citric acid
D&C RED NO. 33
sodium benzoate
sodium citrate
saccharin sodium
Product Characteristics
Color Score
Shape Size
Flavor RASPBERRY (Artificial Red Raspberry Flavor, PFC 9891) Imprint Code
# Item Code Package Description
1 NDC:54838-542-80 473 mL in 1 BOTTLE, PLASTIC
2 NDC:54838-542-40 118 mL in 1 BOTTLE, PLASTIC
Marketing Information
Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date
unapproved other 01/05/2006
Labeler - Silarx Pharmaceuticals, Inc (161630033)
Silarx Pharmaceuticals, Inc

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