In a lot of the cases, you see combinations of antihistamines and decongestants. And decongestants will constrict the blood vessels. So people who are expecting, rhinitis or runny nose ...

They take longer to work than antihistamines and decongestants — people usually notice a difference within twelve hours but the full effect is reached after a few days. As with antihistamines ...

However, the key difference between the medications ... Cetirizine is an over-the-counter (OTC) antihistamine. Pseudoephedrine is a decongestant. Zyrtec-D is an OTC combination medication of ...

that’s a sign of allergies, and you’re not contagious. You can take an over-the-counter antihistamine or a decongestant and head in to work.