Blockage of duodenum, how to stop the vomitting?

My dad has colon cancer, inoperable...Tumor is impinging on duodenum and therefore food he eats is vomited. Nausea meds don’t help. We took him home from hospital . They again gave meds for nausea, but only relief he gets is when he vomits...
Does anyone have any suggestions of meds that would stop vomiting so stomach can pass food slowly to small passage left to intestine? Very frustrating because while want to make him feel comfortable hard to find solution.
Gra0714