Are bone marrow transplants painful?

Side effects: There are many effects which can be unpleasant like nausea, vomiting, diarrhea amd mouth sores. Depending on how the transplant is done the mouth sores can be severe and painful. There can be abdominal pain or bone pain in some patients.

Like a transfusion: Bone marrow transplantation is a long drawn out process. The marrow (or blood stem cells) is actually just infused IV like a blood transfusion. That's the easy part. Often high dose chemotherapy or radiation is given ahead of time. If the marrow comes from someone else then long courses of immune suppressive treatments are needed to control an inflammatory reaction called graft vs host disease.