Jackhammer

Jack Magnus is in a bad way. His drug abuse has taken over his life, and now his only friend is his dead pal Mike, and he sees nefarious forces working against him every which way he turns. Formerly a successful businessman, his only option is to pick up a jackhammer and go on a killing spree in order to quell the voices of paranoia that run rampant within his brain. But when the enemy is your own mind, there's no hope of defeating it, and Jack is drawn ever-further into his downward spiral in this gory B-movie frightfest. (official distributor synopsis)