Well, they are both antihistamines except Coricidin has acetaminophen as well as chlorpheniramine. While Allegra has fexofenadine with no acetaminophen. So it depends on which one you want to use and which one works better. If the Coricidin doesn't seem to be working well enough, try Allegra, if Allegra doesn't work that well, try Zyrtec. It's about trial and error.
Moderator-Allergies/Asthma and Alzheimer's, Co-moderator-UC
Diagnosed Left sided UC in '92 - meds: 6mp, Colazal, Remicade and Bentyl*Unable to tolerate ALL mesalamines*, in '11 diagnosed with IBS, Diverticulosis, Fibromylagia..I also have Sacroiilitis, Scoliosis, Raynauds, OA, PA, Rosacea, Psoriasis, Dry Eye and allergies controlled by Zyrtec and Singular