Are there people who should not take allegra (fexofenadine)?

Yes: With any medication, your physician should be able to provide guidance if a medicine is ok for you to you. In general, any medication that has caused a reaction in the past should not be used again. If you have had a reaction to a medication that is in the same class as the medication on question use caution.

Some: Pku patients: Allegra (fexofenadine) odt contains phenylalanine, other Allegra (fexofenadine) formulations are ok. Pregnancy: it's category c, so pregnant women should avoid and use category b kidney failure: since Allegra (fexofenadine) is excreted by kidneys, a lower dose is used previous adverse reaction to allegra (fexofenadine).