The US Food and Drug Administration said it was a new warning that people who use allergic drugs can experience serious itching when they stop.
The FDA said it was rare, but hundreds of people reported the status after hundreds of people stopped taking cetirizine or levocetirizine every day for at least every day.
The FDA says itching is so bad that medical treatment is needed, the FDA said.
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The institution now reviews the prescription version of the drug, includes a new warning about serious itching risks, and requests a version of the manufacturer who can purchase it without prescription to add a warning label.
The FDA said that users who have experienced severe itching after discontinuing these drugs should contact a health care professional, the FDA said.
The FDA also said that if you are considering taking these allergic drugs regularly, you considered this new risk and discussed with medical service providers in advance.
