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Allegra Side Effects

Generic name: fexofenadine

Medically reviewed by Drugs.com. Last updated on Oct 3, 2023.

Note: This document contains side effect information about fexofenadine. Some dosage forms listed on this page may not apply to the brand name Allegra.

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

Serious side effects of Allegra

Along with its needed effects, fexofenadine (the active ingredient contained in Allegra) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking fexofenadine:

Rare

Other side effects of Allegra

Some side effects of fexofenadine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

Rare

For Healthcare Professionals

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

General

The most commonly reported side effects included headache, drowsiness, dizziness, and nausea.[Ref]

Gastrointestinal

Very common (10% or more): Vomiting (up to 12%)

Common (1% to 10%): Nausea, diarrhea, stomach discomfort[Ref]

Nervous system

Very common (10% or more): Headache (up to 10.3%)

Common (1% to 10%): Drowsiness, dizziness, somnolence[Ref]

Other

Common (1% to 10%): Otitis media, pyrexia, fatigue, extremity pain[Ref]

Respiratory

Common (1% to 10%): Cough, upper respiratory tract infection, rhinorrhea

Frequency not reported: Dyspnea[Ref]

Musculoskeletal

Common (1% to 10%): Back pain[Ref]

Genitourinary

Common (1% to 10%): Dysmenorrhea[Ref]

Psychiatric

Frequency not reported: Insomnia, nervousness, nightmares, sleep disorders or paroniria/excessive dreaming[Ref]

Cardiovascular

Frequency not reported: Palpitations, tachycardia, chest tightness[Ref]

Hypersensitivity

Frequency not reported: Hypersensitivity reactions, angioedema, systemic anaphylaxis[Ref]

Dermatologic

Frequency not reported: Rash, pruritus, flushing[Ref]

Frequently asked questions

References

1. Product Information. Allegra (fexofenadine). Hoechst Marion Roussel. 2001;PROD.

2. Cerner Multum, Inc. UK Summary of Product Characteristics.

3. Cerner Multum, Inc. Australian Product Information.

Further information

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.