Six months after her untimely passing, Lisa Marie Presley‘s cause of death has been revealed. TMZ reports that Presley died due to complications from a bariatric surgical procedure.

TMZ, who received a copy of the toxicology report, which has also been released by the L.A. County Medical Examiner, noted that therapeutic levels of Oxycodone were found in Presley’s blood. Buprenorphine, which is to treat opioid overuse, was also found in her blood.

As opioids often cause constipation, Presley was reported to have suffered a small bowel obstruction, which ultimately led to her death.

The bowel obstruction was in the form of a strangulated bowel, which was caused by adhesion that developed after a gastric bypass procedure years ago.

TMZ also says that there was no sort of drug paraphernalia or narcotics found in Presley’s home on the day she was rushed to the hospital. While at the hospital, Presley was reported to have gone into cardiac arrest.

TMZ reported that Presley had undergone a cosmetic procedure months before her death, and was prescribed opioids. The outlet also noted that Presley apparently had a history of overmedicating, would often forget that she had taken her medications, and then take them again.