Lexapro for digestive issues?

I went to Mount Sinai's Internal Medicine department yesterday. They have a reputation for being among the best in New York for Gastro. issues. I mentioned how I seem to be on a roller coaster with symptoms for a while now (nearly a year) that consist of soft stool and not enough stool during bowel movements, bloating, constipation, general abdominal pain, general weakness, fatigue, and off-balance/unwound feeling. I had mild GERD, but I did the 2.5 month Nexium treatment and I pretty much don't even consider it a real problem anymore. I went through all the tests (HIDA Scan, MRI w/ contrast, etc.) and the only thing that ever showed up was delayed Gastric Emptying on a Gastric Emptying Scan. I've never vomited from this though. I'm currently not on any meds. I was taking nutritional supplements (as I feel I may have a malabsorption of nutrients thing going on) and Mirtazapine for anxiety. My liver function tests came up high so I stopped all pills a week ago.

The new doctor prescribed me Lexapro, and he didn't even mention any Gastro. meds. This took me a little by surprise. Why would they need even mention a Gastro-med, when that is the man issue we were discussing?