Allent Side Effects
Generic Name: brompheniramine / pseudoephedrine
Note: This document contains side effect information about brompheniramine / pseudoephedrine. Some of the dosage forms listed on this page may not apply to the brand name Allent.
For the Consumer
Applies to brompheniramine / pseudoephedrine: oral capsule, oral elixir, oral liquid
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
What are some other side effects of this drug?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Feeling nervous and excitable.
- Not able to sleep.
- Feeling sleepy.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.
For Healthcare Professionals
Applies to brompheniramine/pseudoephedrine: oral capsule, oral capsule extended release, oral elixir, oral liquid, oral suspension extended release, oral syrup, oral tablet, oral tablet chewable, oral tablet extended release
A few cases of dyskinesias and tremors, often of the face, have been reported in patients whose chronic use of brompheniramine extended over a period of up to 10 years. Some of these cases were only partially relieved by discontinuation of the drug. Haloperidol was successful in relieving symptoms in these patients. Spasmodic torticollis has been reported in a child given brompheniramine over an eight month period.[Ref]
Nervous system side effects of brompheniramine have included central nervous system (CNS) depression, resulting in drowsiness and sedation in nearly 50% of patients treated. This effect has often been transient and ceased with continued use. Motor skills have be impaired and patients should be advised to avoid tasks which require attention. Patients should also avoid concomitant use with alcohol and other sedative-hypnotic drugs. Dyskinesias have rarely been reported following chronic use of brompheniramine. Nervous system side effects of pseudoephedrine have included insomnia in up to 30% of patients. Tremor, anxiety, nervousness, and headache have also been reported.[Ref]
Gastrointestinal side effects of brompheniramine have include nausea, dry mouth and constipation. Gastrointestinal side effects of pseudoephedrine have included anorexia and gastric irritation in approximately 5% of patients. Dry mouth, nose, or throat have occurred in up to 15% of patients receiving pseudoephedrine.[Ref]
Cardiovascular effects of brompheniramine have included hypotension, tachycardia, and palpitations. Cardiovascular side effects of pseudoephedrine have included tachycardia. Some patients taking pseudoephedrine have developed hypertension and/or arrhythmias.[Ref]
Pseudoephedrine causes vasoconstriction which generally does not produce hypertension, but may be problematic for patients with preexisting hypertension. Arrhythmias may be produced in predisposed patients. Rarely, pseudoephedrine has been reported to cause coronary artery spasm and chest pain.
One report evaluated the effect with 60 mg of pseudoephedrine on individuals in a hyperbaric chamber at 1 atmosphere (simulated scuba dive to 66 feet of sea water). Pseudoephedrine and depth (stimulated) were found to have significant but opposite effects on heart rate, although these effects were unlikely to be clinically significant during diving.[Ref]
Ocular side effects of brompheniramine have included blurred vision, diplopia, and dry eyes due to anticholinergic effects.[Ref]
Hypersensitivity side effects in patients receiving pseudoephedrine have included fixed drug eruptions.[Ref]
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4. Lyon CC, Turney JH "Pseudoephedrine toxicity in renal failure." Br J Clin Pract 50 (1996): 396-7
5. Thach BT, Chase TN, Bosma JF "Oral facial dyskinesia associated with prolonged use of antihistaminic decongestants." N Engl J Med 293 (1975): 486-7
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7. Dowd J, Bailey D, Moussa K, Nair S, Doyle R, CulpepperMorgan JA "Ischemic colitis associated with pseudoephedrine: Four cases." Am J Gastroenterol 94 (1999): 2430-4
8. Gill ND, Shield A, Blazevich AJ, Zhou S, Weatherby RP "Muscular and cardiorespiratory effects of pseudoephedrine in human athletes." Br J Clin Pharmacol 50 (2000): 205-13
9. Taylor DM, O'Toole KS, Auble TE, Ryan CM, Sherman DR "The psychometric and cardiac effects of pseudoephedrine in the hyperbaric environment." Pharmacotherapy 20 (2000): 1045-50
10. Mores N, Campia U, Navarra P, Cardillo C, Preziosi P "No cardiovascular effects of single-dose pseudoephedrine in patients with essential hypertension treated with beta-blockers." Eur J Clin Pharmacol 55 (1999): 251-4
11. Vidal C, Prieto A, PerezCarral C, Armisen M "Nonpigmenting fixed drug eruption due to pseudoephedrine." Ann Allergy Asthma Immunol 80 (1998): 309-10
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Some side effects may not be reported. You may report them to the FDA.