Key differences between Zyrtec and Zyrtec-D include their active ingredients, the minimum age at which they can be used, purchasing restrictions, and available dosage forms. Moreover, because it ...

Claritin-D, Allegra-D, and Zyrtec-D all contain a decongestant called pseudoephedrine, the same active ingredient that powers Sudafed. It makes your nose feel less stopped up by narrowing the ...