Can you take claritin and xyzal (levocetirizine) on the same day?

Both antihistamines: Both Claritin and xyzal (levocetirizine) are antihistamines. Each should last 24 hours for control of allergic rhinitis symptoms. However, some patients have more severe symptoms or may be using antihistamines for reasons other than allergic rhinitis and may requires more frequent dosing of antihistamines including using Claritin and xyzal (levocetirizine) same day. Recommend this be done under physician supervision.