Xyzal and Zyrtec are antihistamines that relieve allergy symptoms like sneezing and itchy eyes. Xyzal is less likely to cause drowsiness compared to Zyrtec, making it a better choice for some people.

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 ...