Lisa Robin Kelly died almost six months ago, but the cause of her death was finally revealed this week.
The "That '70's Show" star died on August 14th at a Los Angeles alcohol rehabilitation center.
According to the coroner, Kelly died from a combination of "multiple drugs," TMZ reported.
Moreover, her death was ruled an accidental overdose.
Nevertheless, the coroner did not disclose which drugs were present in Kelly's system at the time of her death. The full coroner's report will be released within two weeks, according to TMZ.
The actress, best known for her role on "That '70's Show," had endured a years-long battle against addiction, and was in the process of getting clean when she died.
"Lisa had voluntarily check herself into a treatment facility early this week where she was battling the addiction problems that have plagued her these past few years," her agent Craig Wyckoff said in a statement at the time of her death, according to CNN.
"I spoke to her on Monday and she was hopeful and confident, looking forward to putting this part of her life behind her," he recalled.
Despite Kelly's optimistic attitude, the actress was found dead in the California rehab facility after dying in her sleep, according to TMZ.
Meanwhile, Kelly portrayed Laurie Forman, the sister of Topher Grace's lead character Eric on the hit show.
However, Kelly only appeared on the first three seasons of the show, and was later replaced by a different actress. The FOX series, which ended in 2006, also starred Mila Kunis and Ashton Kutcher.
In the years following "That '70's Show," Kelly grappled with addiction as well as brushes with the law.
In November of 2011, the star was taken into custody along with her husband Robert Joseph Gilliam over a disturbance at their Charlotte, N.C. home. The subsequent mug shot of Kelly later went viral, shocking fans with her gaunt, unusual appearance.
The arrest along with the mug shot led many people to believe that the actress was on drugs. Kelly later admitted a past addiction to drugs, but maintained that she had gotten clean.