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Theraflu Flu & Sore Throat Side Effects

Generic Name: acetaminophen / pheniramine / phenylephrine

Note: This document contains side effect information about acetaminophen / pheniramine / phenylephrine. Some of the dosage forms listed on this page may not apply to the brand name Theraflu Flu & Sore Throat.

For the Consumer

Applies to acetaminophen / pheniramine / phenylephrine: oral packet

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 or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Not able to pass urine or change in how much urine is passed.
  • A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.

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:

  • Dizziness.
  • 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 acetaminophen / pheniramine / phenylephrine: oral powder for reconstitution

Cardiovascular

Cardiovascular side effects of acetaminophen have included two cases of hypotension.

Cardiovascular side effects of phenylephrine have included palpitations, arrhythmias, and cardiovascular collapse with hypotension.[Ref]

Gastrointestinal

Gastrointestinal side effects of acetaminophen have included rare cases of acute pancreatitis.

Gastrointestinal side effects of phenylephrine have included nausea.[Ref]

Genitourinary

Genitourinary side effects of phenylephrine have included dysuria.[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.[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.

In a recent retrospective study of 306 patients admitted for acetaminophen overdose, 6.9% had severe liver injury but all recovered. None of the 306 patients died.

A 19 year old female developed hepatotoxicity, reactive plasmacytosis and agranulocytosis followed by a leukemoid reaction after acute acetaminophen toxicity.[Ref]

Hypersensitivity

Hypersensitivity side effects of acetaminophen have included rare reports of anaphylaxis and fixed drug eruptions.[Ref]

Nervous system

Nervous system side effects of phenylephrine have included headache, dizziness, nervousness, restlessness, tremor, insomnia, convulsions, and central nervous system depression.[Ref]

Renal

Acute tubular necrosis usually occurs in conjunction with liver failure, but has been observed as an isolated finding in rare cases. A possible increase in the risk of renal cell carcinoma has been associated with chronic acetaminophen use as well.

A recent case control study of patients with end-stage renal disease suggested that long term consumption of acetaminophen may significantly increase the risk of end-stage renal disease particularly in patients taking more than two pills per day.[Ref]

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]

Respiratory

Respiratory side effects of acetaminophen have included a case of eosinophilic pneumonia.

Respiratory side effects of phenylephrine have included respiratory difficulty.[Ref]

Psychiatric

Psychiatric side effects of phenylephrine have included hallucinations, fear, and anxiety.[Ref]

General

General side effects of phenylephrine have included pallor and weakness.[Ref]

Dermatologic

Dermatologic side effects associated with acetaminophen includes the risk of rare but potentially fatal serious skin reactions known as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP).[Ref]

References

1. "Product Information. Ah-Chew D (phenylephrine)." WE Pharmaceuticals Inc, Ramona, CA.

2. Brown G "Acetaminophen-induced hypotension." Heart Lung 25 (1996): 137-40

3. Gursoy M, Haznedaroglu IC, Celik I, Sayinalp N, Ozcebe OI, Dundar SV "Agranulocytosis, plasmacytosis, and thrombocytosis followed by a leukemoid reaction due to acute acetaminophen toxicity." Ann Pharmacother 30 (1996): 762-5

4. Lee WM "Medical progress: drug-induced hepatotoxicity." N Engl J Med 333 (1995): 1118-27

5. Kawada A, Hiruma M, Noguchi H, Ishibashi A "Fixed drug eruption induced by acetaminophen in a 12-year-old girl." Int J Dermatol 35 (1996): 148-9

6. Halevi A, BenAmitai D, Garty BZ "Toxic epidermal necrolysis associated with acetaminophen ingestion." Ann Pharmacother 34 (2000): 32-4

7. Eguia L, Materson BJ "Acetaminophen-related acute renal failure without fulminant liver failure." Pharmacotherapy 17 (1997): 363-70

Some side effects of Theraflu Flu & Sore Throat may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.

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