Inactive ingredients

Croscarmellose Sodium, Magnesium Stearate, Maltodextrin, Microcrystalline Cellulose, Polyvinylpyrrolidone, Silica and Stearic Acid.

Pseudoephedrine hydrochloride is an adrenergic (vasoconstrictor) which occurs as fine, white to off white crystals or powder, having a faint characteristic odor. It is very soluble in water, freely soluble in alcohol and sparingly soluble in chloroform. The chemical name is benzenemethanol, α - [1-(methylamino) ethyl]-, [S-(R*,R*)]-, hydrochloride. The structural formula is:

Guaifenesin is an expectorant and occurs as a white to slightly gray, crystalline powder, having a bitter taste. It may have a slight characteristic odor. It is soluble in water, in alcohol, in chloroform, in glycerin and in propylene glycol. The chemical name is: 1,2 propanediol, 3-(2-methoxyphenoxy)-. Chemically, Guaifenesin is 1,2-Propanediol, 3-(2-methoxyphenoxy)-,(+) and has the following structural formula:

Pseudoephedrine

Pseudoephedrine acts as an indirect sympathomimetic agent by stimulating sympathetic (adrenergic) nerve endings to release norepinephrine. Norepinephrine in turn stimulates alpha and beta receptors throughout the body. The action of pseudoephedrine is apparently more specific for the blood vessels of the upper respiratory tract and less specific for the blood vessels of the systemic circulation.The vasoconstriction elicited at these sites results in the shrinkage of swollen tissues in the sinuses and nasal passages. Pseudoephedrine is rapidly and almost completely absorbed from the gastrointestinal tract. Considerable variation in half-life has been observed ( from about 4 1/2 to 10 hours), which is attributed to individual differences in absorption and excretion. Excretion rates are also altered by urine pH, increasing with acidification and decreasing with alkalinization. As a result, mean half-life falls to about 4 hours at pH 5 and increases to 12 to 13 hours at pH 8.

After administration of a 60 mg tablet, 87 to 96% of the Pseudoephedrine is cleared from the body within 24 hours. The drug is distributed to body tissues and fluids, including fetal tissue, breast milk, and the central nervous system (CNS). About 55 to 75% of an administered dose is excreted unchanged in the urine; the remainder is apparently metabolized in the liver to inactive compounds by Ndemethylation, parahydroxylation and oxidative deamination.

Guaifenesin

Guaifenesin is an expectorant which increases respiratory tract fluid secretions and helps to loosen phlegm and bronchial secretions. By reducing the viscosity of secretions, Guaifenesin increases the efficiency of the cough reflex and of ciliary action in removing accumulated secretions from the trachea and bronchi. Guaifenesin is readily absorbed from the gastrointestinal tract and is readily metabolized and excreted in the urine. Guaifenesin has a plasma half-life of one hour. The major urinary metabolite is β -(2-methoxyphenoxy) lactic acid.

Nursing Mothers

Contraindicated because of the higher than usual risk for infants from sympathomimetic amines.

Newborn or Premature Infants

EXEFEN-IR Tablets should not be administered to premature or full-term infants.

General

Use with caution in patients with: hypertension; coronary artery disease; any other cardiovascular disease; glaucoma; prostatic hypertrophy; hyperthyroidism, diabetes.

Before prescribing medication to suppress or modify cough, it is important that the underlying cause of the cough is identified, that modification of the cough does not increase the risk of clinical or physiological complications, and that appropriate therapy for the primary disease is instituted.

Information for Patients

Patients should be instructed to check with physician if symptoms do not improve within 5 days or if fever is present.

Drug Interactions

MAO inhibitors and beta adrenergic blockers increase the effect of sympathomimetics. Sympathomimetics may reduce the antihypertensive effects of methyldopa, mecamylamine, reserpine, and veratrum alkaloids. Care should be taken in administering EXEFEN-IR Tablets concomitantly with other sympathomimetic amines, since their combined effects on the cardiovascular system may be harmful to the patient.

Drug/Laboratory Test Interactions

Guaifenesin may increase renal clearance for urate and thereby lower serum uric acid levels. Guaifenesin may produce an increase in urinary 5-hydroxyindolacetic 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 product should be discontinued 48 hours prior to the collection of urine specimens for such tests.

Carcinogenesis, Mutagenesis, Impairment of Fertility

No long term or reproduction studies in animals have been performed with EXEFEN-IR Tablets to evaluate its carcinogenic, mutagenic and impairment of fertility potential.

Pregnancy

Nursing Mothers

Pseudoephedrine is contraindicated in nursing mothers because of the higher than usual risk for infants from sympathomimetic amines.

Use in the Elderly

The elderly (60 years and older) are more likely to have adverse reactions to sympathomimetics. Overdosage of sympathomimetics in this age group may cause hallucinations, convulsions, CNS depression and death.

Pseudoephedrine

Pseudoephedrine may cause mild central nervous system stimulation, especially in those patients who are hypersensitive to sympathomimetic drugs. Nervousness, excitability, restlessness, dizziness, weakness and insomnia may also occur. Headache and drowsiness have also been reported. Large doses may cause lightheadedness, 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, hallucinations, convulsions, CNS depression, arrhythmias, and cardiovascular collapse with hypotension.

Guaifenesin

No serious side effects have been reported with Guaifenesin.

Treatment

The patient should be induced to vomit, even if emesis has occurred spontaneously; however, vomiting should not be induced in patients with impaired consciousness. Precautions against aspiration should be taken, especially in infants and children.

Ipecac syrup is the preferred method for inducing vomiting. The action of ipecac syrup is facilitated by physical activity and the administration of eight to twelve fluid ounces of water. If emesis does not occur in fifteen minutes, the dose of ipecac should be repeated. Following emesis, any drug remaining in the stomach may be absorbed by activated charcoal administered as a slurry with water.

If vomiting is unsuccessful or contraindicated, gastric lavage should be performed. Isotonic and one-half isotonic saline are the lavage solutions of choice. Saline cathartics, such as milk of magnesia, draw water into the bowel by osmosis and, therefore, may be valuable for their action of rapid dilution of bowel content.

Treatment of the signs and symptoms of overdosage is symptomatic and supportive. Vasopressors maybe used to treat hypotension. Short- acting barbiturates, diazepam or paraldehyde maybe administered to control seizures. Hyperpyrexia, especially in children, may require treatment with tepid water sponge baths or a hypothermic blanket. Apnea is treated with ventilatory support. Stimulants (analeptic agents) should not be used.

Guaifenesin

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 5 grams/kg, produced no signs of toxicity. In severe cases of overdosage, treatment should be aimed at reducing further absorption of the drug. Gastric emptying (Syrup of Ipecac) and/or lavage is recommended as soon as possible after ingestion.

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

Protect from light and moisture. Store at room temperature, USP.