 Story highlights Autopsy reveals no alcohol or illegal drugs in Robin Williams' suicide 
 
 Actor and comedian died August 11 at age 63 
 
 Williams was struggling with depression, anxiety, early Parkinson's, widow says 
 
 Beloved performer was mourned deeply after death 
 
 The death of actor and comedian Robin Williams has officially been ruled a suicide, the coroner in Marin County, California, said Friday. It was prescribed a week before he died.The 63-year-old comedian committed suicide Aug. 11 by hanging himself with a belt in his Marin County home.  Robin Williams Suicide Triggered by Depression, Parkinson's, Paranoia 
 
 Robin Williams -- Suicide Triggered by Depression, Parkinson's, Paranoia 
 
 EXCLUSIVE 
 
 was struggling with his Parkinson's, anxiety, depression and paranoia just before he committed suicide ... this according the Coroner's report.The paranoia has not been previously reported. After he died, Robin's widow Susan Schneider revealed he was in the early stages of Parkinson's According to the report ... Williams had experienced Parkinson's symptoms since 2011 -- he had a tremor in his left arm and movement in his left hand had slowed. Last call made to wife 
 
 The coroner's report said his body was found about 11:45 a.m. by a personal assistant, who used a paperclip to open the locked door of the bedroom where Williams had been sleeping. However, the investigator writes that he later watched the movie in question — the dark comedy World's Greatest Dad — and said the character's son was found "seated on the floor, learning forward with a ligature around the neck secured by a belt" — very similar to the scene of Williams' death. He found the comedian dressed in a long black T-shirt and belted black jeans hanging by a nylon belt in a closet door frame. A cellphone recovered from Williams' pants pocket was dead. After recharging the phone, the coroner searched through its texts and emails and found no messages referencing suicide, the report said. The last call on the phone was made the night before to Williams' wife, Susan, and lasted 38 seconds. Also noteworthy, according to Williams' wife, is that he may have learned of the suicide technique from a movie role in which a character Williams portrayed died from autoerotic asphyxiation. Read more Robin Williams remembered by critics, close friends 
 
 Williams won the Oscar for best supporting actor for his performance as an avuncular psychologist in Good Will Hunting and earned four Academy Award nominations in a career that straddled film and television. Susan told investigators Williams often received gifts from his USO tours with the military, and that the knife was likely from her husband's collection. Complete coverage on Robin Williams
– The coroner in Marin County, Calif., today confirmed that Robin Williams' death was indeed caused by suicide, reports CNN. The 63-year-old had no alcohol in his system when he hanged himself at his home, and the only drugs found were from prescribed medication in "therapeutic concentrations." The coroner lists caffeine, antidepressants, and the Parkinson's drug levodopa. That meshes with reports that Williams had been struggling with anxiety and a recent diagnosis of Parkinson's before his death. The coroner's report also reveals this odd anecdote, as relayed by the Hollywood Reporter: The night before he died, Williams put several wristwatches in a sock and gave them to somebody because he was worried about their safekeeping. TMZ sees that as a sign of paranoia.