The Food and Drug Administration is investigating serious adverse events involving Limbrel, a capsule being marketed as a medical food to manage the metabolic processes associated with osteoarthritis. Health care providers who know their patients are taking the product should advise them to stop taking it immediately, FDA said. While a range of adverse events have been reported, two serious and potentially life-threatening medical conditions are among them: drug-induced liver injury and hypersensitivity pneumonitis. For more information, see the FDA safety alert.