The US Food and Drug Administration (FDA) has issued a warning regarding potential severe itching (pruritus) in patients who discontinue long-term use of the antihistamines cetirizine (Zyrtec) and levocetirizine (Xyzal). This warning follows the FDA’s review of 209 reports of pruritus worldwide from 2017 to 2023, with 197 cases occurring in the United States. The reports indicate that symptoms emerged within days after stopping the medication, with individuals using these drugs for durations ranging from just a week to as long as 23 years.
The FDA’s data suggests that the likelihood of developing pruritus increases with the length of time a person has taken these medications. Consequences of the itching can severely impact daily life, with some cases leading to disability, hospitalization, and even thoughts of self-harm. While the exact reasons for this reaction remain unclear, the FDA acknowledges a plausible link between the cessation of these antihistamines and the onset of itching.
According to the FDA, cetirizine and levocetirizine are commonly prescribed, with about 26.8 million prescriptions and an additional 62.7 million over-the-counter sales reported in 2022. The agency reassured that pruritus appears to be a rare occurrence relative to overall usage, and many patients found relief by either resuming the medications or tapering off carefully after restarting.
Manufacturers will now be required to update labeling on both prescription and OTC medications to warn of the itching risk. Healthcare professionals are advised to discuss the benefits and risks associated with these antihistamines with patients considering long-term use.
Concerns regarding the implications of this warning have been raised by experts, including Adam Friedman, MD, from George Washington University, who pointed out missing details in the FDA’s communication. He emphasized the lack of information regarding dosages, reasons for use, and demographic data of affected patients, making it challenging to draw definitive conclusions.
This warning doesn’t just reflect a current concern; similar reports of severe itching have previously emerged from studies in the Netherlands and analyses conducted by FDA staff in past years. In light of the allergy season, there are fears that this warning might deter patients from using much-needed antihistamines.
The evolving discussion highlights the importance of ongoing communication between healthcare providers and patients, ensuring that individuals can make informed decisions about their treatment while weighing the potential risks and benefits.