Gastritis Support Group
Gastritis is a medical term for inflammation of the lining of the stomach. It means that white blood cells move into the wall of the stomach as a response to some type of injury. Gastritis has many underlying causes, from infection with the bacterium H. pylori, bile reflux, or excessive consumption of alcohol or certain foods or drugs like aspirin.
On related subject, Chlorella (broken cell wall) protects the liver, so I would recommend it to anyone on drugs with even mild liver interaction. Or just for no reason except additional safety.
The only side-effect is cosmetic - green poop.
Chlorella was also documented as helping treat existing damage of the liver. You may want to tell your friend that... ask the hospital if the son can start taking chlorella (broken cell wall version).