Hi
It depends what causes the pain. If it is created by our mind / is psychosomatic or not . Our brain can create all sorts of illnesses / pains : cancer, migraine, eczema etc. The list goes on and on... This is subconscious of course. In this case the question is : why this person needs create a illness for live or be happy ?
Otherwise when someone takes a placebo well, that fools the mind of the person, so he /her really believes to have took a true medicine. As a result he / her feels better !
Have a nice day
Catherine