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Allerx Dose Pack - Pm Tablets

AM Dose - 120 mg pseudoephedrine HCl and 2.5 mg methscopolamine nitrate
PM Dose - 8 mg chlorpheniramine maleate and 2.5 mg methscopolamine nitrate


Each AM Tablet contains:

Pseudoephedrine HCl .......................... 120 mg

Methscopolamine Nitrate ...................... 2.5 mg

Each PM Tablet contains:

Chlorpheniramine Maleate ........................ 8 mg

Methscopolamine Nitrate ....................... 2.5 mg

Chlorpheniramine maleate is an antihistamine having the chemical name 2-pyridinepropanamine, gamma-(4-chlorophenyl)-N, N-dimethyl-, (Z)-2-butenedioate (1:1).


Pseudoephedrine hydrochloride is a nasal decongestant. Chemically it is [S-(R*,R*)]-(alpha)-[1-(methyl-amino)ethyl] benzenemethanol hydrochloride.


Methscopolamine nitrate is an anticholinergic having the chemical name 3-oxa-9-azonlatricyclo [ 2 4 ] nonane, 7-(3-hydroxy-1-oxo-2-phenylpropoxy)-9, 9-dimethyl-nitrate,[7(S)-1(1(alpha), 2(beta), 4(beta), 5(alpha), 7(beta))].


Inactive Ingredients:

AM Tablets: Each Yellow AM Tablet contains Ethylcellulose, Stearic Acid, Dibasic Calcium Phosphate, D&C Yellow #10 (aluminum lake) Dye, and Magnesium Stearate.

PM Tablets: Each Blue PM Tablet contains Methocel™, Dibasic Calcium Phosphate, FD&C Blue #1 Lake Dye, Stearic Acid, and Magnesium Stearate.

Clinical Pharmacology

Pseudoephedrine HCl is an indirect-acting sympathomimetic amine that exerts a decongestant action on the nasal mucosa. It does this by vasoconstriction, which results in reduction of tissue hyperemia, edema, nasal congestion, and an increase in nasal airway patency. In the usual dose it has minimal vasopressor effects. Pseudoephedrine is rapidly and almost completely absorbed from the gastrointestinal tract. It has a plasma half-life of 6 to 8 hours. Alkaline urine is associated with slower elimination of the drug. The drug is distributed to the body tissues and fluids, including the central nervous system (CNS). Approximately 50% to 75% of the administered dose is excreted unchanged in the urine; the remainder is apparently metabolized in the liver to inactive compounds by N-demethylation, parahydroxylation, and oxidative deamination.

Chlorpheniramine maleate is an alkylamine-type antihistamine. This group of antihistamines is among the most active histamine antagonists and is generally effective in relatively low doses.

Methscopolamine nitrate is a quaternary ammonium derivative of the anticholinergic scopolamine which possesses the peripheral actions of the belladonna alkaloids, but does not exhibit the central actions because of its lack of ability to cross the blood-brain barrier. Its antimuscarinic effect causes drying of mucous secretions.

Indications and Usage

For the temporary relief of symptoms associated with allergic rhinitis, vasomotor rhinitis, sinusitis, and the common cold.


This product is contraindicated in patients with hypersensitivity to pseudoephedrine HCl, methscopolamine nitrate, and chlorpheniramine maleate. AlleRx™ is contraindicated in patients with severe hypertension, severe coronary artery disease, patients on monoamine oxidase inhibitor (MAOI) therapy or within 14 days of stopping monoamine oxidase inhibitor (MAOI) therapy, and in nursing mothers on monoamine oxidase inhibitor (MAOI) therapy. AlleRx™ is also contraindicated in patients with narrow-angle glaucoma, urinary retention, peptic ulcer, and during an asthmatic attack.


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

Co-administration of sildenafil citrate and other organic nitrates has been shown to potentiate the hypotension effects of nitrates. Co-administration of AlleRx™ and sildenafil citrate has not been studied. Therefore, the use of sildenafil citrate and AlleRx™ together is not recommended.


General:   Should be used with caution in patients with diabetes mellitus, hypertension, cardiovascular disease, and hyperactivity to sympathomimetic amines. Antihistamines may cause drowsiness, and ambulatory patients who operate machinery or motor vehicles should be cautioned accordingly.

Drug Interactions

Monoamine oxidase inhibitors (MAOI) and beta adrenergic blockers increase the effect of sympathomimetics. Sympathomimetics may reduce the antihypertensive effects of methyldopa, mecamylamine, reserpine, and veratrum alkaloids. Concomitant use of antihistamines with alcohol, tricyclic antidepressants, barbiturates, and other CNS depressants may have an addictive effect.

Concomitant use of sildenafil and other organic nitrates has been shown to potentiate the hypotension effects of nitrates.

Pregnancy Category C:   It is not known whether AlleRx™ Tablets can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. AlleRx™ Tablets should be given to a pregnant woman only if clearly needed.

Nursing Mothers:   (Check CONTRAINDICATIONS ). It is not known whether this combination drug is excreted in human milk. However, pseudoephedrine administered alone distributes into the breast milk of lactating human females; therefore, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use:   The safety and effectiveness in children under 12 years of age have not been established.

Geriatric Use:   The elderly (60 years and older) are more likely to experience adverse reactions to sympathomimetics. Overdosage of sympathomimetics in this age group may cause hallucinations, convulsions, CNS depression, and/or death. AlleRx™ is known to be substantially excreted by the kidneys, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

Adverse Reactions

Adverse reactions include drowsiness, lassitude, nausea, giddiness, dryness of mouth, blurred vision, cardiac palpitations, flushing, and increased irritability or excitement (especially in children). Some individuals may display sympathomimetic amine effects such as tachycardia, palpitations, headache, dizziness, or nausea. Sympathomimetics have been associated with certain untoward reactions including fear, anxiety, nervousness, restlessness, tremor, weakness, pallor, respiratory difficulty, dysuria, insomnia, hallucinations, convulsions, CNS depression, arrhythmias, and cardiovascular collapse with hypotension. Urinary retention may occur in patients with prostatic hypertrophy. Antihistamines and anticholinergics may cause drowsiness, dizziness, blurred vision, and excessive dryness of the nose, throat, and mouth.


The treatment of overdosage should provide symptomatic and supportive care. Induction of emesis and gastric lavage may be performed if the patient is alert and seen within early hours after ingestion. Drug remaining in the stomach may be absorbed by the administration of activated charcoal. Stimulants should not be used because they may precipitate convulsions. If convulsions or marked CNS excitement occurs, treatment with appropriate measures is indicated. Since the effects of AlleRx™ last up to 12 hours, the patient should be monitored for at least that length of time and treated as necessary.

Dosage and Administration

Adults and adolescents 12 years of age and over:   One yellow AM Tablet in the morning and one blue PM Tablet in the evening. AlleRx™ is not recommended for children under 12 years of age.

How Supplied

(NDC 63824-067-20) AlleRx™ Tablets 10-Day Treatment Regimen, containing 20 controlled-release Tablets as follows:

10 yellow, elongated AM Tablets debossed with "Adams" on one side and "006" on the other side, each containing 120 mg of pseudoephedrine HCl and 2.5 mg of methscopolamine nitrate.

10 blue, elongated PM Tablets debossed with "Adams" on one side and "007" on the other side, each containing 8 mg of chlorpheniramine maleate and 2.5 mg of methscopolamine nitrate.

Store at controlled room temperature between 15° and 30°C (59° and 86°F).

Dispense as a complete 10 day dose pack.

Keep out of reach of pediatric population.

Adams Laboratories, Inc.,

Fort Worth, TX 76155

Licensed under U.S. Patent No. 6,270,796

Rx Only                                         071902


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  2. Drug Facts and Comparisons. St. Louis, Mo: Facts and Comparisons, a Walters Kluwer Company; 2001:698.
  3. Bantz EW, Dowlen WK, Chadwick EW, Nelson HS. Chronic chlorpheniramine therapy: subsensitivity, drug metabolism, and compliance. Ann Allergy. 1987;59:341-346.
  4. Witek TJ Jr, Canestrari DA, Miller RD, Yang JY, Riker DK. Characterization of daytime sleepiness and psychomotor performance following H 1 receptor antagonists. Ann Allergy Asthma Immunol. 1995;74:419-426.
  5. Clarke CH, Nicholson AN. Performance studies with antihistamines. Br J Clin Pharmacol. 1978;6:31-35.
  6. Meltzer EO, Tyrell RJ Jr, Rich D, Wood CC. A pharmacologic continuum in the treatment of rhinorrhea: the clinician as economist. J Allergy Clin Immunol. 1995;95:1147-1152.

Adams Laboratories, Inc.

© 2002 Adams Laboratories, Inc., Fort Worth, Texas 76155

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.