Robin Williams hanged himself with a belt in his own bedroom on August 11 of this year. The actor had been battling depression after learning that he was in the early stages of Parkinson’s disease.

According to investigators, closed bottle of Seroquel, a drug to treat bipolar disorders and depression, was found in his room. Williams had been prescribed the medication a week before he died.

Williams cause of death was determined to be asphyxia. There were superficial cuts on his wrists, and a pocket knife was found nearby. His personal assistant had grown concerned when he hadn’t awakened that morning and went to check on him. Williams had been dead for hours.

Now a toxicology report has been released that affirms that there were indeed no illegal drugs nor alcohol found in Williams’ system at the time of his death. The only substances were pharmaceuticals in “therapeutic concentrations,” which indicates only the dosage he was prescribed.

Williams had struggled with alcoholism and drug dependency in the past. Some had expressed concern that he may have succumbed to these in the end. But the report indicates a man who took his medicine properly, but looked into a bleak future and saw no further.

Williams’ wife Susan Schneider said he had seemed excited when she saw him the night before. The web history of his iPad showed that he had made an online search for discussions of medications including Lyrica and propranolol.

President Barack Obama said of Williams that he “made us laugh. He made us cry.”

“He gave his immeasurable talent freely and generously to those who needed it most – from our troops stationed abroad to the marginalized on our own streets.”

Robin Williams was cremated and his ashes were scattered in the San Francisco Bay.