Dad has sigmoid colon cancer, and its now really progressing in the last few days, he now can't eat or drink anything other than water, as he feels nauseous. The Doc's put him on Oromorph as an interim to him starting the subcutaneous Morphine for his pain.  However he's been sick and its a cola colour? But with no food in him,  what is causing this? He had done this before taking the Oromorph too so cant blame that. any help would be appreciated. Thanks Mandy x