<s>[INST] Have lower back pain and upper abdominal ache urine has turned dark yellow have been taken a laxative for the last couple of days and some hydrocodone for arteitis all meds by script except m magnesia over counter concerned that pain was really bad 2nights ago has gone down a little but still uncomfortable especially upper right side [/INST] Hello I have studied your case, You are having gastric upset I will advise starting antacids [proton pump inhibitors like] omeprazole 20 mg twice a day. Sucralfate will protect gastric mucosa and will give protective covering. If not relieved you may need to do USG abdomen. Pain may also from renal or policy pain. Hope this answers your query. If you have additional questions or follow-up queries then please do not hesitate in writing to us. I will be happy to answer your queries. Wishing you good health. Take care </s>