 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed (See How to Use section).The uses of Zyrtec Oral: Cetirizine is an antihistamine used to relieve allergy symptoms such as watery eyes, runny nose, itching eyes/nose, sneezing, hives, and itching. It works by blocking a certain natural substance (histamine) that your body makes during an allergic reaction.Cetirizine does not prevent hives or prevent/treat a serious allergic reaction (such as anaphylaxis). If your doctor has prescribed epinephrine to treat allergic reactions, always carry your epinephrine injector with you. Do not use cetirizine in place of your epinephrine. How to use Zyrtec If you are taking the over-the-counter product to self-treat, read all directions on the product package before taking this medication. If you have any questions, consult your pharmacist. If your doctor has prescribed this medication, take it as directed, usually once daily. If you are using the chewable tablets, chew each tablet well and swallow. If you are using the rapidly-dissolving </s>