(CNN) A California-based company is voluntarily recalling cough syrup because it contains morphine, according to the Food and Drug Administration.

The agency announced that Master Herbs, Inc. distributed 100ml bottles of Licorice Cough Liquid with the opioid, but it wasn't declared on the product's label.

The cough syrup was distributed to Chinese grocery stores in California, New Jersey, Hawaii, Illinois, Ohio and Nevada, according to the FDA.

Morphine can be deadly if it's consumed unwittingly, the FDA said. It can also cause respiratory depression and severe allergic reactions.