Actor Rob Schneider has blamed his good friend Robin Williams' tragic death on a drug he was taking to combat the early symptoms of Parkinson's Disease.

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Schneider, 50, who has been friends with the Mrs. Doubtfire star for the past 20 years since they first met on Saturday Night Live, took to Twitter on Thursday, Aug. 14, to talk Parkinson's drugs and the role they played in his pal's death.

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"Now that we can talk about it. #RobinWilliams was on a drug treating the symptoms of Parkinson's. One of the SIDE-EFFECTS IS SUICIDE!" he wrote.

"The Evil pharmaceutical industry ADMITS TO OVER 100,000 people in the USA DIE A YEAR FROM "PRESCRIPTION" DRUGS!! #RobinWilliams."

Schneider's outburst was hot on the heels of Williams' wife Susan Schneider's revelation that her husband had been suffering from the degenerative neurological disease, although he had not wanted his diagnosis to become public knowledge yet.

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"Robin's sobriety was intact," his wife wrote in a statement earlier that day. "And he was brave as he struggled with his own battles of depression, anxiety, as well as early stages of Parkinson's Disease, which he was not yet ready to share publicly.”

Fellow Parkinson's sufferer Michael J. Fox expressed his shock at the discovery that Williams had been diagnosed. "Stunned to learn Robin had PD. Pretty sure his support for our Fdn predated his diagnosis," the 53-year-old wrote. "A true friend; I wish him peace."

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Williams’ body was found in his Northern California home on Monday, Aug. 11. His death appears to be the result of suicide.

Marking a week since the sad news first broke, Schneider finished his slew of Twitter tributes to his late friend with one final memorial message in the early hours of Monday, Aug. 18. “We are only allowed to mourn for 7 days so... Just thank and hug the ones you love and who have touched your lives! Thx4ever #RobinWilliams,” he wrote.