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Mucinex Allergy Side Effects

Generic Name: fexofenadine

Note: This page contains information about the side effects of fexofenadine. Some of the dosage forms included on this document may not apply to the brand name Mucinex Allergy.

In Summary

Common side effects of Mucinex Allergy include: headache. Other side effects include: otitis media. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to fexofenadine: oral capsule, oral suspension, oral tablet, oral tablet disintegrating

In addition to its needed effects, some unwanted effects may be caused by fexofenadine (the active ingredient contained in Mucinex Allergy). In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking fexofenadine:

  • Chest tightness
  • feeling of warmth, redness of the face, neck, arms and occasionally, upper chest
  • large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • shortness of breath, difficult or labored breathing

Minor Side Effects

Some of the side effects that can occur with fexofenadine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Vomiting
Less common:
  • Back pain
  • body aches or pain
  • chills
  • coughing
  • diarrhea
  • difficulty with moving
  • dizziness
  • ear congestion
  • earache
  • fever
  • headache
  • joint pain
  • loss of voice
  • muscle aching or cramping
  • muscle pains or stiffness
  • nasal congestion
  • nausea
  • pain in arms or legs
  • pain or tenderness around eyes or cheekbones
  • painful menstrual bleeding
  • redness or swelling in ear
  • ringing or buzzing in ears
  • runny or stuffy nose
  • sleepiness or unusual drowsiness
  • sneezing
  • sore throat
  • stomach upset
  • swollen joints
  • unusual feeling of tiredness or weakness
  • viral infection (such as cold and flu)
  • Nervousness
  • rash
  • sleeplessness
  • terrifying dreams
  • trouble sleeping

For Healthcare Professionals

Applies to fexofenadine: oral capsule, oral suspension, oral tablet, oral tablet disintegrating


Gastrointestinal side effects have included nausea and dyspepsia in approximately 1.5% of patients.[Ref]

Nervous system

Nervous system side effects have included drowsiness in 1.3% of patients. Dizziness and headache have also been reported.[Ref]


Genitourinary side effects have included dysmenorrhea at a rate of 1.3%.[Ref]


Hypersensitivity side effects have included rare reports of rash, urticaria, and pruritus. Other hypersensitivity reactions have included angioedema, chest tightness, dyspnea, flushing, and systemic anaphylaxis.[Ref]


Respiratory side effects have included nasopharyngitis and upper respiratory tract infection.[Ref]


Musculoskeletal side effects have included myalgia, back pain, and pain in extremity.[Ref]


1. "Product Information. Allegra (fexofenadine)." Hoechst Marion-Roussel Inc, Kansas City, MO.

2. Takahashi H, Ishida-Yamamoto A, Iizuka H "Effects of bepotastine, cetirizine, fexofenadine, and olopatadine on histamine-induced wheal-and flare-response, sedation, and psychomotor performance." Clin Exp Dermatol 29 (2004): 526-32

3. Weiler JM, Bloomfield JR, Woodworth GG, Grant AR, Layton TA, Brown TL, McKenzie DR, Baker TW, Watson GS "Effects of fexofenadine, diphenhydramine, and alcohol on driving performance - A randomized, placebo-controlled trial in the Iowa Driving Simulator." Ann Intern Med 132 (2000): 354-63

Not all side effects for Mucinex Allergy may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

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. 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.