Authorities say 33-year-old Michael Lasiter rushed into the Denny's restaurant late Friday and started stabbing himself in one arm with a butter knife he grabbed from a table.
They say that when that knife didn't work Lasiter took a butcher knife from the kitchen and dug it into his arm.
Police Sgt. Brian Findlen says Lasiter told officers he thought he needed to amputate his arm to keep himself from dying from the cocaine injection.
Lasiter was taken to a hospital for treatment of severe cuts.