A laxative sold at major U.S. retailers is being recalled after "serious adverse reactions” were reported.

All flavors of Magnesium Citrate Saline Laxative Oral Solution are affected by the recall, which the Food and Drug Administration said is being initiated over concerns about bacterial contamination. The product is sold at CVS, Harris Teeter, Kroger, Rite Aid, Walgreens and Walmart under a variety of generic brand names, usually in 10-ounce packages.

Tennessee-based Vi-Jon LLC, the manufacturer, is aware of three reports of serious adverse reactions potentially related to the product, and it is investigating the reports, the FDA said.

The agency said immunocompromised patients who consume the product may be at increased risk for invasive infections caused by the bacterium Gluconacetobacter liquefaciens, which could lead to serious, life-threatening adverse health consequences.