I've been taking cetirizine for years along with other drugs and now am dealing with blood sugar being higher than it should be . I recently discovered that all but one of my meds affects my glucose . anyway ..... I digress...... I quit taking the cetirizine and about two days later started itching all over . it was going on for four days until I figured out what I had done differently and that was quitting the cetirizine . so , I restarted it and the itching stopped within a few hours of taking it.