Hello As you mentioned that your mother is having stomach irritation , so it is very difficult to make any assessment about the diagnosis ,because of these problems mentioned in query. But you mentioned that your mother is taking UNISTAR i.erosuvastatine. This drug is a lipid lowering agent and used in patient having HYPERLIPIDAEMIAS , so this is a dyslipidaemic agent . In this type of disease patient should eat fat free diet and do regular exercise. Neopride , the 2nd medicine is used as an anti psychotic drug, dyspepsia, gastro-esophageal reflex , irritable bowel syndrome ( constipation & diarrhea). For any prescription physical examination as well clinical examination is important . In your mother case doctor prescribed medicine according to his knowledge . If your mother is not responding to these drugs , consult one more physician and get his opinion. Good luck.