November 08, 2014 - 10:40 GMT hellomagazine.com An autopsy has revealed that Robin Williams had no alcohol or illegal drugs in his system when he committed suicide in August Robin Williams was clear of alcohol and illegal drugs when he took his own life, an autopsy has revealed. On Friday it was announced that post-mortem examination results released by Marin County sheriff's office found that the actor had taken prescription medication, but that they were not the cause of his death. A coroner ruled that Mrs Doubtfire star Robin's passing was suicide resulting from asphyxia due to hanging. An autopsy on Robin's body found no alcohol or illegal drugs in his system Tests showed that the 63-year-old had two types of antidepressants in his system when he died, as well as a Parkinson's medication, caffeine and another ingredient found in tea and cocoa. Robin's wife Susan Schneider said that in the run up to his death the actor and comedian had been struggling with depression, anxiety and a recent Parkinson's diagnosis prompting him to enter a rehabillitation centre in July. The coroner's report says Susan told police that Robin, who sought help for drug and alcohol abuse several years ago, did not enter the programme due to recent substance abuse, but to reaffirm his previous rehabilitation. The report also claims Susan said her husband was having trouble sleeping and had shown increased signs of paranoia before he committed suicide. Robin's wife Susan was the last person to see him alive Susan was the last person to see Good Morning Vietnam star Robin alive when she went to bed on 10 August at their home in Tiburon, Northern California. The following morning, however, Robin's assistant came to the house and found the actor dead in another bedroom after he failed to respond when she knocked on the door.