Levocetirizine should not be used in these groups of patients: Patients with known hypersensitivity to levocetirizine, cetirizine or any ingredients in the formulation; Adults and children 12 years of age and older with end-stage renal failure (creatinine clearance less than 10 ml/min) or undergoing dialysis; Children younger than 12 years of age with renal impairment.