Injecting the painkiller Opana ER can lead to a serious blood disorder that can result in kidney failure or death, the Food and Drug Administration (FDA) announced Thursday.

Opana is an opioid that contains the ingredient oxymorphone, Reuters reports. The drug is made by Endo Pharmaceuticals. Injecting Opana can cause thrombotic thrombocytopenic purpura, which causes clots to form in small blood vessels throughout the body. These clots limit or block blood flow to the organs, the article explains.

Opana ER is a pill meant to be taken orally. It causes the blood clotting disorder only when it is abused by being crushed and injected intravenously, according to the FDA. The pill has an extended-release design, but crushing it releases the drug all at once.

Law enforcement officials are alarmed by the rise of Opana abuse, which they said started after OxyContin was changed in late 2010 to make that drug more difficult to snort or inject for a heroin-like high. OxyContin is a brand of oxycodone.

Opana abuse can be deadly because it is more potent, per milligram, than OxyContin and users who are not familiar with how strong it is may be vulnerable to overdosing.

Endo Pharmaceuticals has announced it is reformulating the drug. The pill will be more difficult to crush, and will turn gooey if liquid is added to it. Opana is prescribed for chronic back pain, as well as pain related to cancer and osteoarthritis.