Mylan Pharmaceuticals is recalling a single lot of anti-anxiety medication Alprazolam – commonly sold as Xanax. According to their statement, Mylan "believes the recalled product could potentially contain a foreign substance, causing a risk of illness." No word on what that mysterious substance could be though

The voluntary recall includes bottles containing 500 half milligram tablets.The lot number is 8-0-8-2-7-0-8 and the expiration date is September 2020. Mylan says the pills were distributed in the U.S. between July and August.

If you have been prescribed this medication, check the lot number on the side of the bottle. If they match, return them immediately to the pharmacy that issued it to you.