It is the theory from Sigmund Freud and it is about the development of different symptoms that can replace old symptoms when they have cleared after the treatment. It takes place on the unconscious level.

SYMPTOM SUBSTITUTION: "When the Symptom substitution takes place, the doctors may fail to understand if it is related to a new sickness or to the old sickness. "
Cite this page: N., Pam M.S., "SYMPTOM SUBSTITUTION," in, April 13, 2013, (accessed June 22, 2021).