It is contraindicated in patients with known hypersensitivity to montelukast, levocetirizine, to other piperazine derivatives or to any of the excipients. Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine. Also, contraindicated in patients with severe renal impairment at less than 10 mL/min creatinine clearance.