Would pepsin gi (8mg zinc with 29.5mg l-carnosine) be a helpful supplement to take if i currently have gastritis?

Possibly, but: PepZin is a compound of L-carnitine and Zinc marketed in Japan for treatment of stomach distress and peptic ulcer disease. Studies support it's healing effect in a number of gastric conditions. If you've self diagnosed your condition as gastritis you should check with a physician to be sure you don't have an ulcer or H.pylori related gastritis. Most U.S. physicians are not familiar with PepZin.