What are some natural remedies for GERD?

My boss has it. Has an appt in a month, but since he’s a nice guy, I was thinking to help him out a bit until he goes to the doc.
Thanks
He’s not fat by any means and he doesn’t smoke. He stresses out a lot. Again, he is going to see a gastro in a month, but I wanted to get him something in the meantime. I don’t know who Tony is…
Oh, and he’s been on Nexium for… ever…