Jeanie, I am so sorry Maggie is ill.
I would not force food on her. I have given those meds without food when pups were ill. Just keep a close eye on her...check her gums to make sure they are not dry and sticky to the touch as that would indicate dehydration. Hopefully, the meds will kick in, she will feel a bit better and eat something.
You might want to try baby food. Sometimes they like that.
Someone mentioned meds to increase appetite: you might ask your vet about Mirtazapine. It is an amazing medicine....in dogs it controls nausea and also stimulates the appetite. I have seen it work in some very ill dogs!