Discover how Allegra-D® 12 Hour Tablets provide powerful relief from tough allergy symptoms and nasal congestion, keeping you comfortable and alert. Zyrtec vs. Claritin vs. Allegra: Which is the best allergy medicine? In general, Zyrtec, Claritin, and Allegra all work similarly well for treating allergies. But some studies suggest Allegra might work slightly better for eye-related symptoms. And Claritin may be slightly less effective than other similar antihistamines. Discover how Allegra-D® 24 Hour Tablets act as a powerful nasal congestion medicine, providing relief from tough allergy symptoms when you need cold and allergy medicine. Allegra and Allegra-D are over-the-counter allergy medications used to treat seasonal allergy symptoms. Learn how they work, possible side effects, and more. Allegra-D (fexofenadine and pseudoephedrine) is used to treat sneezing, hives, runny or stuffy nose and other symptoms of allergies. Includes Allegra-D side effects, interactions and indications. Allegra-D Allergy and Congestion package insert / prescribing information for healthcare professionals. Includes: indications, dosage, adverse reactions and pharmacology. Allegra-D (fexofenadine / pseudoephedrine) is a combination of two medications that work together to relieve allergy symptoms. Fexofenadine is a second-generation antihistamine. It blocks histamine, a natural chemical in your body that can cause allergy symptoms like itchiness, itchy eyes, or runny nose. Pseudoephedrine is a decongestant. It tightens blood vessels in the nose to relieve sinus. Allegra-D allergy medicine starts working in one hour to give you non-drowsy relief from allergy symptoms, plus sinus pressure and nasal congestion. Best of all, Allegra-D works for a full 24 hours. Allegra-D allergy medicine starts working in one hour to give you non-drowsy relief from allergy symptoms, plus sinus pressure and nasal congestion. Best of all, Allegra-D works for a full 24 hours. Shop Allegra-D 12HR Allergy Relief & Decongestant Extended Release Tablets, Non-Drowsy at CVS Pharmacy and enjoy FREE shipping on all eligible orders.