U.S. health regulators on Tuesday issued an import alert for drug ingredients and products related to Xylazine, used largely as a veterinary tranquilizer but has been a drug of abuse, to restrict its unlawful entry into the United States.

The Food and Drug Administration (FDA) said its move aims to prevent the drug from entering the U.S. market for illicit purposes, while maintaining availability for its legitimate uses in animals.

Under the alert, the FDA will do an entry review of evidence offered by importers if incoming Xylazine is properly labeled, not adulterated, and for legitimate use.

Xylazine is approved by the FDA only for veterinary use and German drugmaker Bayer's animal sedative drug Rompun is among the drugs which are based on Xylazine.

Xylazine has increasingly been found in illicit drugs and detected in overdose deaths, the agency said in its statement, adding that its staff may detain shipments found in violation of the law during the review.

The drug can depress breathing, blood pressure, heart rate and body temperature to critical levels and when taken by people through injections may result in severe skin wounds that could lead to amputation and become life-threatening.

"The FDA remains concerned about the increasing prevalence of Xylazine mixed with illicit drugs, and this action is one part of broader efforts the agency is undertaking to address this issue," FDA Commissioner Robert Califf said in the statement. 

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