The execution of Brett Hartman is scheduled for 10 a.m. Tuesday at the Southern Ohio Correctional Facility in Lucasville.
Prisons spokeswoman JoEllen Smith says Hartman has been calm and cooperative since arriving Monday.
Smith says Hartman slept for about three hours early Tuesday.
He declined breakfast before starting visits with an aunt, a sister and a friend Tuesday morning.
Prison staff checked Hartman’s veins twice on Monday and determined they were accessible and shouldn’t pose problems during the execution.
Hartman took two doses of an anti-anxiety drug Monday, which is offered to inmates under Department of Rehabilitation and Correction policy.