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Generic name: hrine hydrochloride and guaifenesin
Dosage form: oral liquid
Drug class: Upper respiratory combinations

Medically reviewed by Last updated on Sep 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.

ACTIVE INGREDIENTS: Each 5 mL (teaspoonful) contains:

Phenylephrine Hydrochloride ..... 7.5 mg
Guaifenesin ..... 100 mg

INACTIVE INGREDIENTS: Citric Acid, Orange Flavoring, Sorbitol Solution, Propylene Glycol, Purified Water, Saccharin Sodium, Sodium Benzoate, and Sodium Chloride.

Phenylephrine hydrochloride

Benzenemethanol,3-hydroxy-α-[(methylamino) methyl]-hydrochloride (R)-., is an adrenergic, which occurs as white or practically white, odorless crystals having a bitter taste. It is freely soluble in water and alcohol.


1,2-Propanediol, 3-(2-methoxyphenoxy)-, (±)-., is a white to slightly gray, crystalline powder, having a bitter taste. It may have a slight characteristic odor. It is soluble in water, alcohol, chloroform, glycerin, and propylene glycol.

Crantex - Clinical Pharmacology

Phenylephrine HCI is a sympathomimetic which acts predominantly on alpha receptors and has little action on beta receptors, therefore it functions as an oral nasal decongestant with minimal CNS stimulation. Guaifenesin has an expectorant action which increases the output of respiratory tract fluid by reducing adhesiveness and surface tension. Sinus and bronchial drainage is improved and dry, non-productive coughs become more productive and less frequent.

Indications and Usage for Crantex

For temporary relief of symptoms associated with the common cold, influenza, and bronchitis.


Crantex Liquid® is contraindicated in infants and newborns, and in patients with a known hypersensitivity to any of the components. It is also contraindicated in patients with severe hypertension, severe coronary artery disease, hyperthyroidism, and in patients on MAO inhibitor therapy (or for 14 days after stopping MAOI therapy). Patient idiosyncrasy to adrenergic agents may be manifested by insomnia, dizziness, weakness, tremor, or arrhythmias.


Drug Interactions

MAO inhibitors (or for 14 days after stopping MAOI therapy) and beta adrenergic blockers increase the effects of sympathomimetics. Sympathomimetics may reduce the antihypertensive effects of methyldopa, mecamylamine, reserpine, and veratrum alkaloids.

Drug Laboratory Test Interactions

Guaifenesin may increase renal clearance for urates and thereby lower serum uric acid level.

Guaifenesin may produce an increase in urinary 5-hydroxyindoleacetic acid and may therefore interfere with the interpretation of this test for the diagnosis of carcinoid syndrome. It may also falsely elevate the VMA test for catechols. Administration of this drug should be discontinued 48 hours prior to the collection of urine specimens for such tests. Stimulants, such as phenylephrine, are banned and tested for by the U.S. Olympic Committee (USOC) and the National Collegiate Athletic Association (NCAA).

Carcinogenesis, Mutagenesis and Impairment of fertility

No adequate and well controlled studies have been conducted to determine whether the components of Crantex Liquid® have a potential for carcinogenesis, mutagenesis, or impairment of fertility.

Pregnancy Category C

Animal reproduction studies have not been conducted with this product. It is also not known whether Crantex Liquid® can cause fetal harm when administered to pregnant women or can affect reproduction capacity. This product should not be given to a pregnant woman.

Nursing Mothers

Due to the possible passage of the ingredients into breast milk, this product should not be given to nursing mothers.

Pediatric Use

Safety and effectiveness in the pediatric population, under 6, have not been established.


Do not exceed recommended dosage. If nervousness, dizziness, or sleeplessness occur, discontinue use and consult a doctor. If symptoms do not improve within 7 days or are accompanied by a fever, consult a doctor.

Adverse Reactions

Mild central nervous system stimulation, especially in those patients who are hypersensitive to sympathomimetic drugs, may occur. Hyperreactive individuals may display ephedrine-like reactions such as tachycardia, palpitations, headache, dizziness, or nausea. Nervousness, excitability, restlessness, weakness, and insomnia may also occur. Headache and drowsiness have also been reported. Large doses may cause light-headedness, nausea and/or vomiting. Sympathomimetic drugs have also been associated with certain untoward reactions including fear, anxiety, tenseness, restlessness, tremor, weakness, pallor, respiratory difficulty, dysuria, insomnia, hallucination, convulsion, CNS depression, arrhythmias and cardiovascular collapse with hypotension.


Signs and Symptoms

Overdosage with sympathomimetic amines can cause cardiac arrhythmias, cerebral hemorrhage and pulmonary edema. It can also cause palpitations, restlessness, dizziness, tremor, vomiting, fear, labored breathing, headache, dryness of mouth, pallor, weakness, panic, anxiety, confusion, hallucinations, delirium, hyperactive reflexes, talkativeness, irritability and insomnia. Cardiovascular and renal effects include difficulty in urination, headache, flushing, palpitation, cardiac arrhythmias, hypertension with subsequent hypotension and circulatory collapse. Gastrointestinal effects include dry mouth, anorexia, nausea, vomiting, diarrhea, and abdominal cramps.

Overdosage with guaifenesin is unlikely to produce toxic effects since its toxicity is low. Guaifenesin, when administered by stomach tube to test animals in doses up to 0.5 g/kg produced no signs of toxicity.


The patient should be induced to vomit, even if emesis has occurred spontaneously. Pharmacologic vomiting by the administration of ipecac syrup is a preferred method, however, vomiting should not be induced in patients with impaired consciousness. Precautions against aspiration must be taken, especially in infants and children. Following emesis, any drug remaining in the stomach may be absorbed by activated charcoal administered as slurry with water. Treatment of the signs and symptoms of overdosage is symptomatic and supportive.

Crantex Dosage and Administration

Adults and Children 12 years and older 1-2 teaspoons every 4-6 hours, not to exceed 8 teaspoons in a 24 hour period. Children 6-12 years old ½ to 1 teaspoon every 4-6 hours, not to exceed 4 teaspoons in a 24 hour period. This product is not indicated for use in children under 6 years of age. (see PRECAUTIONS, Pediatric Use.) KEEP THIS AND ALL MEDICATIONS OUT OF THE REACH OF CHILDREN. IN CASE OF ACCIDENTAL OVERDOSAGE, CONTACT A POISON CONTROL CENTER AND SEEK PROFESSIONAL ASSISTANCE IMMEDIATELY.


Store at 25°C (77°F); excursions permitted to 15°-30° (59°- 86°F). See USP Controlled Room Temperature. Protect from freezing.


How is Crantex Supplied

Crantex Liquid® is clear, orange flavored and supplied in bottles of 16 fl. oz. (473 mL) NDC 51991-233-16.

Distributed by: Breckenridge Pharmaceutical, Inc., Boca Raton, FL 33487

Manufactured by:
Tri-Med Laboratories, Inc.,
Somerset, NJ 08873

All prescription substitutions using this product shall be pursuant to state statutes as applicable. This is not an Orange Book product.

REV. 4/08


Pharmaceutical, Inc.

NDC 51991-233-16


ACTIVE INGREDIENTS: Each 5 mL (teaspoonful)
Phenylephrine Hydrochloride ..... 7.5 mg
Guaifenesin ..... 100 mg

Flavoring, Sorbitol Solution, Propylene Glycol,
Purified Water, Saccharin Sodium, Sodium Benzoate,
and Sodium Chloride.

Dye Free • Sugar Free
Alcohol Free

Rx Only
This container is not for
dispensing to patients.

16 fl oz (473 mL)

phenylephrine hydrochloride liquid
Product Information
Product Type HUMAN PRESCRIPTION DRUG LABEL Item Code (Source) NDC:51991-233
Route of Administration ORAL DEA Schedule
Active Ingredient/Active Moiety
Ingredient Name Basis of Strength Strength
Phenylephrine Hydrochloride (Phenylephrine) Phenylephrine Hydrochloride 7.5 mg in 5 mL
Guaifenesin (Guaifenesin) Guaifenesin 100 mg in 5 mL
Inactive Ingredients
Ingredient Name Strength
Citric Acid Monohydrate
Propylene Glycol
Saccharin Sodium
Sodium Benzoate
Sodium Chloride
Product Characteristics
Color Score
Shape Size
Flavor ORANGE Imprint Code
# Item Code Package Description
1 NDC:51991-233-16 473 mL in 1 BOTTLE
Marketing Information
Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date
Unapproved drug other 02/01/2002 09/30/2011
Labeler - Breckenridge Pharmaceutical, Inc. (150554335)
Name Address ID/FEI Operations
Trimed 182050567 MANUFACTURE
Breckenridge Pharmaceutical, Inc.

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