Senior Superintendent of Police (SSP) Sandeep Sharma confirmed the incident and said a search operation has been launched to trace the prisoner.
He said jail authorities had brought four prisoners for treatment in the civil hospital this afternoon.
"One of the prisoners, identified as Pankaj who was suffering from hepatitis C virus, manage to flee from the hospital laboratory when a technician was taking his blood samples," he said.
He is a resident of Danush mand locality of Jalandhar and was undergoing jail term in a murder case.