Teenagers and young adults suffering from severe, scarring acne may ultimately lose the most effective treatment for the condition.

Swiss-based Roche Holding quietly pulled its blockbuster drug Accutane off the market in June amid early signs that the drug may be linked to inflammatory bowel disease. And last week, a study was released that quantified those risks, finding that users of the medication have almost twice the odds of developing a serious bowel disorder as nonusers.

For now, generic versions are still available, but the latest troubles could lead to the withdrawal of the controversial medication considered the treatment of last resort for acne so damaging it can lead to pitting of the face and a lifetime of anguish.

In its tumultuous 27-year history, the drug, also known as isotretinoin, has been found to cause serious birth defects if taken during pregnancy and to possibly increase the risk of depression, including suicidal behavior. Women who take it must register with the government, sign a consent form saying that they understand the medication's risks, use two forms of birth control, and submit to monthly pregnancy tests.