How fast does a generic drug maker have to update its product labeling to match changes to the equivalent brand-name medication? The question has arisen during a lawsuit by a California woman who suffered a fracture while using a generic version of osteoporosis medication Fosamax.

It is alleged that although Fosamax updated its labeling to include newly discovered side effects of the drug, namely the risk of a femur fracture, the makers of the generic medication she had been prescribed had not updated these new risk factors in a timely manner.

According to court documents, the generic labels were updated six weeks after the brand-name version had changed its labels to include the new risk information, and that delay caused the woman to suffer harm. The requisite timeliness of updating such warnings has become a central issue in the case, which the Supreme Court has been asked to review.