Levocetirizine is an active isomer of cetirizine that selectively competes with histamine for H1-receptor sites on effector cells in the GI tract, blood vessels and respiratory tract.

Adult
PO
Seasonal allergic rhinitis, chronic idiopathic urticaria: 2.5-5 mg once daily in the evening.

Adverse drug reactions: Somnolence, dizziness, fatigue, cough, urinary retention, blurred vision, extrapyramidal symptoms.

Adapted from CIMS Drug Information System. Internet. Accessed on January 10, 2016.