What's DGL?
I've tried aloe it helps a little bit...
Curable? Yes, though how depends on the reason for the gastritis. Slow digestion, H. Pylori, stomach flu, stress, diet... all possible reasons. Chronic? Again, depends on the reason.
I recommend you take things to help soothe the gastric lining, like aloe vera and DGL. However, you should work with your doctor for a resolution to the condition.
Good luck.