Philip Seymour Hoffman died on Feb. 2, possibly from an overdose of heroin, though autopsy. The accomplished actor said he had given up drugs and alcohol years ago, at just 22 years old. As his friend Seth Mnookin wrote on Slate, "... one day in 2012, he began popping prescription pain pills. And now he's dead." Hoffman's is only the latest in a growing list of celebrity deaths in which painkillers were implicated.