The M.D.

"The M.D.: A Horror Story" by Thomas M. Disch is a 1991 horror novel about Billy Michaels, a boy who receives a magical caduceus from the god Mercury, granting him the power to heal or harm. The story follows his life as he uses the staff, which requires him to inflict sickness to replenish its power, leading to a dark journey from childhood cruelty to adult greed and monstrous acts, including creating plagues and running concentration camps. It's the second book in Disch's "Supernatural Minnesota" series, known for its dark humor, social commentary, and exploration of morality.