Levocetirizine for chronic idiopathic urticaria: a review.

Only recently available on the US market, levocetirizine has emerged as an effective new option in the treatment of chronic idiopathic urticaria (CIU). Levocetirizine is the active isomer of cetirizine and demonstrates twice the affinity for the H1 receptor compared with the parent compound. In the treatment of CIU, levocetirizine has consistently demonstrated high response rates, fast onset, and a favorable side effect profile.