Anxiety-drug Xanax has been recalled due to a possible "foreign substance," the Food and Drug Administration announced last week.

Mylan Pharmaceuticals, citing a small chance of infection in recalling the batch of Alprazolam, which is sold under the brand Xanax, urged wholesalers to look for the potentially contaminated pills, writing in the notice they should, "immediately examine your inventory, quarantine, and discontinue distribution of these lots."

It is unclear what the foreign material is.

"Clinical impact from the foreign material, if present, is expected to be rare, but the remote risk of infection to a patient cannot be ruled out," reads the recall notice posted to the FDA's website Saturday.

"Consumers should contact their physician or healthcare provider if they have experienced any problems that may be related to using this drug product," the notice adds.

Consumers who want to return the product can call (888) 843-0255. Consumers with questions about the recall can call Mylan at 800-796-9526 (Monday through Friday, 8 a.m.-5 p.m. ET) or by emailing customer.service@mylan.com.

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