What is cetirizine. Cetirizine or cetirizine hydrochloride (cetirizine HCL) is a non-drowsy antihistamine medicine that relieves the symptoms of allergies by blocking the effects of the chemical histamine in your body. The Best Allergy Medicine. Fighting allergies can feel like a war on pollen (and kittens), yet the real enemy lies within. For those of us with allergies, our immune systems overreact to pollen, animal dander, mold, and dust. Get set for summer with our range of stylish outdoor furniture. We’ve got garden décor sorted with pretty pots and ornaments, as well as outdoor lighting to create an ambience after the sun sets. Hi Niman, Thanks for the comment! I am a bit confused about what you are asking… Histamines can cause watery eyes, nasal congestion and sore throat. Zyrtec and Alcohol. Drinking alcohol can increase certain side effects of cetirizine. Zyrtec and Drug Interactions. Many drugs can interact with Zyrtec. Uses. This combination medication is used to temporarily treat runny nose, coughing, and sneezing caused by the common cold, allergies, hay fever, and other breathing illnesses. I LOVE this!! Last year my daughter had the flu for 6 weeks, and she was 16 at the time. I had it too, but fought it off faster then she did. I tried to get her to take lemon and honey but she didn’t. If you or your child has a minor health complaint and you're already entitled to a free prescription, you may also be able to get free non-prescription medicines and treatments through the little-known NHS minor ailments scheme. Our editors independently research, test, and recommend the best products; you can learn more about our review process here. We may receive commissions on purchases made from our chosen links. Benadryl can cause mild or serious side effects. The following list contains some of the key side effects that may occur while taking Benadryl.