Chronic “sour” stomach problems?

Hi. I am 43 and have only been on methadone 5 months for a chronic pain disorder related to my disease. I was being overly medicated on 30 mg, and I was sleeping all day. Cognitively I was one tenth of what I am normally, but the final straw was i was having so much stomach trouble, nausea that I could barely get myself to eat or drink. I am slim 5'8" 120 lbs (female) and in addition to my illness I knew if I didn't get off of it I would waste away. I have often described it as sour stomach, rocks in my stomach, something rotting in my stomach, etc...SO I am in the withdrawal phase and I have yet to get relief from the stomach issues. My diet consists of vanilla yogurt with granola, dry cereal, and toast. I drink Vitamin waters with Stevia so I can stay really hydrated and I am able to keep those down. I have heard over and over that methadone is horrible for the stomach. I have found that dramamine,, even compared to prescription anti-nausea drugs, helps not only with the nausea but also with the pain. Right now it's late, I need food to take my meds, so I am eating dry cereal, which really helps. I also heard that Boost the over the counter really sweet drink is packed full of Vitamins and all stuff, so that according to my nurse, you can live on Boost alone and stay healthy. Having something in my stomach helps the pain, so I eat whatever sounds remotely appealing. You could whip up the boost with ice to tone down the sugary taste of it. Let me know if this works or is helpful. OR if you have found any tricks. Best of luck to you. Eva