Common side effects of Zyrtec include sleepiness, tiredness, and dry mouth. Zyrtec can interact with other medications that cause drowsiness, such as opioids and sleeping pills. Rarely, Zyrtec can ...

SaveHealth, a prescription savings card website, compares Xyzal vs. Zyrtec. Xyzal (levocetirizine) and Zyrtec (cetirizine) are antihistamines widely used to treat allergy symptoms like sneezing, runny ...