The Tony Award-winner, who wrote the books for stage musicals based on John Waters' movies "Hairspray" and "Cry-Baby," was 58 when he died Monday morning.
An autopsy will be conducted to determine the exact cause of his death, but police told the Daily News it was not suspicious.
O'Donnell was a 1976 graduate of Harvard University and a frequent contributor to "The Harvard Lampoon." He also penned the novels "Getting Over Homer" and "Let Nothing You Dismay."
Swim Week Miami Beach 2014 [PHOTOS]