Giraldo's family was at his side at the time of his passing, according to TMZ.
According to the New York Post, Giraldo was found unconscious in his hotel room in East Brunswick, NJ on Saturday evening following "a wild party."
"It was a like a zoo here," an eyewitness told the Post.
Paramedics were reportedly able to resuscitate Giraldo, who had been staying at the hotel for a four-night appearance at a local comedy club, but he had remained in critical condition at Robert Wood Johnson University Hospital in New Brunswick.
The overdose was not a suicide attempt, according to Giraldo's representative.
"Greg was one of the most talented comedians of our time. He was truly brilliant. His work will surely continue to influence and inspire us. We will miss our friend," Last Comic Standing's producers told Reality TV World in a written statement.
"Our thoughts and prayers are with his family."
Prior to becoming a comedian, Giraldo -- who also regularly appeared on Comedy Central's celebrity roasts -- had been an attorney who attended Harvard Law School.
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