Have Medical Questions? Ask a Doctor Online!
This is Dr. David
I am sorry about your son.
having severe gastritis, vomiting, not drinking water can cause him to be dehydrated and to loose weight quickly.
dehydration is a serious issue.
he need to go to the ER and get blood tests to check his BUN and creatinine levels which could be elevated as signs for dehydration.
he needs an MRI scan of your spine to look for herniated disks or pinched nerves in his spine which can be causing him pain.
when was his last MRI scan of his spine?