Dilated blood vessels can cause nasal congestion (stuffy nose). Zyrtec-D is a combination medicine used to treat cold or allergy symptoms such as nasal and sinus congestion, sneezing, itching, watery eyes, or runny nose. Zyrtec-D may also be used for purposes not listed in this medication guide. Zyrtec-D Allergy Relief & Nasal Decongestant Tablets combine the proven allergy relief of Zyrtec with a powerful nasal decongestant to relieve allergy symptoms and nasal congestion. ZYRTEC-D ® Allergy Relief and Nasal Decongestant Tablets contain 5 mg cetirizine HCl antihistamine and 120 mg pseudoephedrine decongestant for relief from nasal congestion, sinus pressure, and allergy symptoms caused by pollen, dust, pet dander, mold, and other airborne allergens. Zyrtec-D allergy relief, plus nasal decongestant, works on allergy congestion in as little as 30 minutes. Allergy medicine relieves allergy & congestion symptoms due to both indoor & outdoor allergies. Learn about Zyrtec-D (cetirizine / pseudoephedrine) usage and dosing. Read the latest news and reviews about the drug as well as potential side effects and popular alternatives. Zyrtec-D Allergy Relief & Nasal Decongestant Tablets combine the proven allergy relief of Zyrtec with a powerful nasal decongestant to relieve allergy symptoms and nasal congestion. Shop for Zyrtec D at Walmart.com. Save money. Live better.