Police said the 26-year-old man, who was lodged in Tiruthuraipoondi sub Jail, was admitted to the Tiruvarur Medical College Hospital here and added that his condition was reported to be stable.
He reportedly took the step as none of his relatives took any steps to get him released.
The man had been arrested along with five others in connection with the kidnapping of a 10-month-old girl child of Veeran Nagar near Tiruthuraipoondi on August 14 this year.