Flu HBP Maximum Strength Side Effects
Generic name: acetaminophen / chlorpheniramine / dextromethorphan
Medically reviewed by Drugs.com. Last updated on Jul 30, 2023.
Note: This document provides detailed information about Flu HBP Maximum Strength Side Effects associated with acetaminophen / chlorpheniramine / dextromethorphan. Some dosage forms listed on this page may not apply specifically to the brand name Flu HBP Maximum Strength.
Applies to acetaminophen / chlorpheniramine / dextromethorphan: oral liquid, oral suspension.
Important warnings
This medicine can cause some serious health issues
Do not use this medicine if you have taken an MAO inhibitor in the past 14 days.
A dangerous drug interaction could occur.
MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.
Do not take more of this medication than is recommended. An overdose of acetaminophen can damage your liver or cause death. Call your doctor at once if you have nausea, pain in your upper stomach, itching, loss of appetite, dark urine, clay-colored stools, or jaundice (yellowing of your skin or eyes).
In rare cases, acetaminophen may cause a severe skin reaction. Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling.
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
In rare cases, acetaminophen may cause a severe skin reaction that can be fatal. This could occur even if you have taken acetaminophen in the past and had no reaction. Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling. If you have this type of reaction, you should never again take any medicine that contains acetaminophen.
Stop using the medicine and call your doctor at once if you have:
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severe headache, seizure (convulsions);
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fast, pounding, or uneven heartbeats;
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confusion, hallucinations, severe dizziness or drowsiness, slow or shallow breathing;
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tremor, restless muscle movements;
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little or no urination;
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flu symptoms, easy bruising, unusual bleeding, pale skin, weakness, feeling light-headed; or
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nausea, pain in your upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).
Side effects such as dry mouth, constipation, and confusion may be more likely in older adults.
Common side effects may include:
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headache, sleep problems (insomnia);
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upset stomach, diarrhea or constipation;
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dry eyes, blurred vision, dry mouth or nose;
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mild dizziness or drowsiness, trouble concentrating;
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feeling restless or excited (especially in children); or
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mild skin rash.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.
For healthcare professionals
Applies to acetaminophen/chlorpheniramine/dextromethorphan: oral liquid, oral suspension, oral syrup, oral tablet.
Cardiovascular adverse events
Two cases hypotension have been reported following the administration of acetaminophen. Both patients experienced significant decreases in blood pressure. One of the two patients required pressor agents to maintain adequate mean arterial pressures. Neither episode was associated with symptoms of anaphylaxis. Neither patient was rechallenged after resolution of the initial episode.[Ref]
Cardiovascular side effects of acetaminophen have included two cases of hypotension.
Cardiovascular side effects of chlorpheniramine have included hypotension, tachycardia, and palpitations.[Ref]
Nervous system
Nervous system side effects of chlorpheniramine have included depression resulting in drowsiness in 75% or more of treated patients. Dyskinesias have rarely been reported following chronic use of chlorpheniramine.
Nervous system side effects of dextromethorphan have included drowsiness and dizziness. Other side effects such as excitation, mental confusion, and opiate-like respiratory depression have been rare and occurred at higher dosages. In some cases of abuse, patients experienced euphoria, hyperactivity, mania, and auditory and visual hallucinations.[Ref]
Few cases of dyskinesias and tremors, often of the face, have been reported in patients whose chronic use of chlorpheniramine extended over a period of 3 to 10 years. Some of these cases were only partially relieved by discontinuation of the drug. Haloperidol was successful in relieving symptoms.[Ref]
Gastrointestinal
Gastrointestinal side effects of acetaminophen have been rare, except in alcoholics and after overdose. Cases of acute pancreatitis have been reported rarely with the use of acetaminophen.
Gastrointestinal side effects of chlorpheniramine have included dry mouth and constipation in up to one-third of treated patients.
Gastrointestinal side effects of dextromethorphan have included stomach upset.[Ref]
One study has suggested that acetaminophen may precipitate acute biliary pain and cholestasis. The mechanism of this effect may be related to inhibition of prostaglandin and alterations in the regulation of the sphincter of Oddi.[Ref]
Hypersensitivity
Hypersensitivity side effects of acetaminophen have included anaphylaxis and fixed drug eruptions.
Hypersensitivity side effects of dextromethorphan have included rare reports of fixed-drug eruptions.[Ref]
Genitourinary
Genitourinary side effects of chlorpheniramine have included dysuria, urinary hesitancy, and decreased urine flow.[Ref]
Respiratory
Respiratory side effects of acetaminophen have included a case of eosinophilic pneumonia.[Ref]
Hepatic
Hepatic side effects of acetaminophen have included severe and sometimes fatal dose dependent hepatitis in alcoholic patients. Hepatotoxicity has been increased during fasting. Several cases of hepatotoxicity from chronic acetaminophen therapy at therapeutic doses have also been reported despite a lack of risk factors for toxicity.[Ref]
Alcoholic patients may develop hepatotoxicity after even modest doses of acetaminophen. In healthy patients, approximately 15 grams of acetaminophen is necessary to deplete liver glutathione stores by 70% in a 70 kg person. However, hepatotoxicity has been reported following smaller doses. Glutathione concentrations may be repleted by the antidote N-acetylcysteine. One case report has suggested that hypothermia may also be beneficial in decreasing liver damage during overdose.[Ref]
Renal
Renal side effects of acetaminophen have included acute tubular necrosis and interstitial nephritis. Adverse renal effects are most often observed after overdose, after chronic abuse (often with multiple analgesics), or in association with acetaminophen-related hepatotoxicity.[Ref]
Hematologic
Hematologic side effects of acetaminophen have included rare cases of thrombocytopenia. Methemoglobinemia with resulting cyanosis has also been observed in the setting of acute overdose.
Hematologic side effects of chlorpheniramine have included bone marrow suppression, thrombocytopenia, and aplastic anemia.[Ref]
A fatal case of agranulocytosis has been reported in a patient taking chlorpheniramine, pseudoephedrine, acetaminophen, dextromethorphan, phenylpropanolamine, and aspirin. Chlorpheniramine was felt to be the cause.[Ref]
Dermatologic
Dermatologic side effects of acetaminophen have included erythematous skin rashes. Bullous erythema and purpura fulminans have also been reported.[Ref]
Metabolic
Metabolic side effects of acetaminophen have included metabolic acidosis following a massive overdose.[Ref]
In the case of metabolic acidosis, causality is uncertain as more than one drug was ingested. The case of metabolic acidosis followed the ingestion of 75 grams of acetaminophen, 1.95 grams of aspirin, and a small amount of a liquid household cleaner The patient also had a history of seizures which the authors reported may have contributed to an increased lactate level indicative of metabolic acidosis.[Ref]
Ocular
Ocular side effects of chlorpheniramine have included blurred vision, diplopia, and dry eyes due to anticholinergic effects.[Ref]
References
1. "Product Information. Chlor-Trimeton (chlorpheniramine)." Schering-Plough
2. (2005) "Product Information. Coricidin (acetaminophen-chlorpheniramine)." Schering-Plough Healthcare Products
3. "Product Information. Tylenol Childrens Plus Cough and Runny Nose (acetaminophen/chlorpheniramine/DM)." McNeil Consumer Healthcare
4. Bantz EW, Dolen WK, Chadwick EW, Nelson HS (1987) "Chronic chlorpheniramine therapy: subsensitivity, drug metabolism, and compliance." Ann Allergy, 59, p. 341-6
5. Schuller DE, Turkewitz D (1986) "Adverse effects of antihistamines." Postgrad Med, 79, p. 75-86
6. Stubb S, Reitamo S (1990) "Fixed-drug eruption due to dextromethorphan ." Arch Dermatol, 126, p. 970-1
More about Flu HBP Maximum Strength (acetaminophen / chlorpheniramine / dextromethorphan)
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- Compare alternatives
- Imprints, shape & color data
- Dosage information
- During pregnancy
- Drug class: upper respiratory combinations
Patient resources
Other brands
Coricidin HBP Maximum Strength Flu, Triaminic Multi-Symptom Fever, Tylenol Children’s Cold + Cough + Runny Nose, Vicks Formula 44 Custom Care Cough & Cold PM
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Further information
Flu HBP Maximum Strength side effects can vary depending on the individual. 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.