Hi Dr. Rynne, My Mother-in-law (age 87) Suffers From Chronic

Hi Dr. Rynne, my mother-in-law (age 87) suffers from chronic nausea (about 6 months). She keep getting passed around between her primary care physician and the GI. They think maybe she's dehydrated. She does have problem with constipation, but we have assured she is drinking lots of water now. GI said he would see her in 6 months and explore neurological if hydration and rx review didn't work. Today she could hardly get out of bed. As you might imagine, her appetite is declining. She had colon cancer about 8 yrs. ago and had about 1 ft. removed. We are very concerned. Any advice?