Gastritis remedies..

My husband has gastritis and it just keeps getting worst and worst his new insurance doesn't kick in until 08/01 so he refuses to go to the doctor right now, any advices of how to treat it? He has been taken a lot of Tums but it seems that they don't help any more. He was in a lot of pain last night he couldn't sleep. I'm worried and I just wanna help him. :(