When people doesn't feel pain

Congenial insensitivity to pain, is also know as congenial analgesia is one or more rare condition that a person cannot feel physical pain. Feeling physical pain is vital for life, CIP is extremely dengerous condition.

Cause :

It may be that condition which is caused by increased production of endonephrine in the brain...in that case naloxone may be a treatment but it doesn't always work

Treatment:

The opioid antagonist naloxone allowed a women with congenital insensitivity to pain to experience it for the first time.