FDA Warns of Rare Severe Itching After Stopping Zyrtec, Xyzal

The U.S. Food and Drug Administration (FDA) has issued a warning that patients who stop taking the allergy medications cetirizine (Zyrtec) or levocetirizine (Xyzal) after long-term daily use may experience a rare but severe side effect: intense, widespread itching known as pruritus. This itching typically begins within two days of discontinuation and has been reported in over 200 cases since 2017, with symptoms severe enough to require medical intervention including hospitalization or causing significant impairment to quality of life. The FDA is updating prescription and over-the-counter labeling to include this risk and advises patients to consult healthcare professionals before starting long-term use and if severe itching develops after stopping the medications. Most patients found relief by restarting the medication, sometimes tapering off more gradually, though the exact mechanism causing this reaction remains unknown. Despite the rarity of this side effect compared to the millions of doses used annually, the FDA emphasizes awareness among both patients and healthcare providers about this potential withdrawal effect. The agency encourages informed discussions regarding the benefits and risks of long-term use of these common antihistamines.