Patients ceasing long-term use of oral allergy medications cetirizine (Zyrtec) or levocetirizine (Xyzal) may experience rare but severe itching called pruritus, according to an FDA alert.
RT’s Three Key Takeaways:
- Rare but severe itching — The FDA warns that stopping long-term daily use of cetirizine (Zyrtec) or levocetirizine (Xyzal) may cause rare but serious pruritus, sometimes requiring medical intervention.
- Evidence and mechanism — The FDA identified 209 global cases, mostly in the US, supporting a causal link between discontinuation and itching, though the biological mechanism remains unknown.
- Updated safety guidance — New prescription and OTC labels will include warnings, and patients are advised to consult healthcare professionals if severe itching occurs, with restarting or tapering the medicine shown to relieve symptoms in many cases.
The US FDA is warning that patients stopping the prescription and OTC oral allergy medicines cetirizine (Zyrtec) or levocetirizine (Xyzal) after long-term use may experience rare but severe itching, according to an agency alert.
Cetirizine and levocetirizine are antihistamines approved to treat seasonal allergies, called seasonal allergic rhinitis, in adults and children 2 years and older. The medicines are also approved to treat year-round allergies, called perennial allergic rhinitis, and chronic hives, called chronic idiopathic urticaria, in patients 6 months and older.
The itching, also called pruritus, has been reported in patients who used these medicines daily, typically for at least a few months and often for years. Patients did not experience itching before starting the medicines. Reported cases were rare but sometimes serious, with patients experiencing widespread, severe itching that required medical intervention. As a result, we are revising the prescription cetirizine and levocetirizine prescribing information to include a new warning about this risk. We will subsequently request that manufacturers add a warning about pruritus to the Drug Facts Label of the OTC versions.
FDA Findings
The FDA identified 209 cases worldwide (197 in the United States) of pruritus after stopping use of cetirizine (n=180), levocetirizine (n=27), or both (n=2) reported to FDA between April 25, 2017, and July 6, 2023. This number includes only reports submitted to FDA* so there may be additional cases of which we are unaware (see Data Summary). The majority of these medications are OTC; it is estimated that the total OTC purchases for these products in 2022 was more than 60 million packages. Pruritus after medicine discontinuation appears to be rare compared to how often the medicine is used (see Facts about Cetirizine and Levocetirizine). The underlying mechanism for this risk is unknown, but our evaluation supports a causal relationship between stopping cetirizine or levocetirizine and pruritus. Many reports described widespread pruritus that required medical intervention after stopping these medicines, with a large number describing significant and persistent impact on quality of life and ability to function. Most patients who experienced pruritus after medicine discontinuation reported using these medicines for more than 3 months; however, some experienced this reaction after less than 1 month of use.
Restarting the medicine resolved pruritus in most individuals, and tapering off the medicine after restarting it resolved symptoms in some who tried this approach. Other than prolonged use, we have not identified any clear risk factors for pruritus after medicine discontinuation.
*The cases were reported to the FDA Adverse Event Report System (FAERS) database.
FDA Actions
The FDA is adding a warning about the risk of pruritus after stopping long-term use of prescription cetirizine or levocetirizine to the prescribing information to increase awareness about this rare but serious reaction. The updated prescribing information also states that pruritus symptoms may improve with restarting the medicines. We will also request that manufacturers add a warning about pruritus to the Drug Facts Label of OTC cetirizine and levocetirizine. In the meantime, we want to make the public aware of this risk. We will follow up when additional information becomes available.
FDA Recommendations for Patients
Patients should contact a healthcare professional if they develop severe itching after stopping prescription or OTC cetirizine or levocetirizine. Patients should know that itching typically occurred within a few days of stopping these medicines after daily use for a few months to years. Individuals planning on long-term use of cetirizine or levocetirizine, especially for more than a few months, should discuss the benefits and risks with a healthcare professional, who can provide advice based on personal needs.
FDA Recommendations for Healthcare Professionals
Health care professionals should discuss the risk of pruritus after stopping cetirizine or levocetirizine with patients when prescribing or recommending these medicines, especially if planned for chronic use, and with those who indicate they are using OTC versions. Encourage patients to contact you if they experience severe itching after stopping cetirizine or levocetirizine. Effective treatments for pruritus have not been evaluated. However, symptoms resolved in most patients who restarted the medicine and in some who tapered off the medicine after restarting it.
References
- IQVIA National Prescription Audit (NPA) database. Data year 2022. Data extracted August 2024. IQVIA home page available at https://www.iqvia.com/insights/the-iqvia-institute/available-iqvia- data.
- IQVIA Consumer Health Insights and Private-Label Ingredient-Level Report. Data year 2022. Data extracted September 2023. IQVIA home page available at https://www.iqvia.com/library/fact- sheets/iqvia-consumer-health-market-insights.
