My grandma has been taking morphine for chronic pain for a few weeks, has developed terrible nausea and isn't eating anything - don't think she's really had anything for at least 2 days. She's been to the doctor and he's taken her off the morphine, given her paracetemol and codeine (cocodamol?) and anti-nausea meds but she isn't feeling any better. Will the anti-nausea meds take a while to kick in? Is there anything she can do to lessen the nausea, or things that are good to try and eat? She's pretty underweight to begin with and very bad at drinking fluids so am very worried about her.