Unexpected withdrawal symptom happening to people who stopped taking this common pill

If you’ve recently experienced severe itching after stopping an oral allergy medication, you’re not alone.

The U.S. Food and Drug Administration is warning that patients who are no longer taking cetirizine (Zyrtec) or levocetirizine (Xyzal) after long-term use “may experience rare but severe itching.”

Between April 25, 2017, and July 6, 2023, the administration received 209 worldwide reports of pruritus — itchy skin — after patients stopped taking either (or both) medications. Of the 200-plus reports, 197 stemmed from the United States.

The FDA’s announcement defines “long-term use” as daily use ranging from a few months to a few years, although some patients experienced the reaction after less than one month of taking either medication.

“Reported cases were rare but sometimes serious, with patients experiencing widespread, severe itching that required medical intervention,” the announcement reads. It goes on to state that a “large number” of patients described the itching has having a “significant and persistent impact on quality of life and ability to function.”

The FDA reported that the cause of the itching is currently unknown, although there are indications of a “causal relationship” between the side effect and stopping taking cetirizine or levocetirizine. Due to the new data, the FDA is revising the prescribing information for these allergy medications to include a warning about the risk of pruritus.

Anyone experiencing severe itching after stopping prescription or over the counter cetirizine or levocetirizine should contact their health professional, the FDA advised.

“Restarting the medicine resolved pruritus in most individuals, and tapering off the medicine after restarting it resolved symptoms in some who tried this approach,” the announcement states. “Other than prolonged use, we have not identified any clear risk factors for pruritus after medicine discontinuation.”