Brief Answer: It looks like gastritis Detailed Answer: Hi, This is Dr. Ashish Verma, a general surgeon, answering to your query. It would have been good if you had mentioned your treatment history - if you are on pain killers to manage aggressive osteoarthritis This severe stabbing pain just under your stermum which is aggravated by food is classical of gastritis or we call it as peptic ulcer disease of stomach. You may have developed this problem secondary to NSAIDs (analgesics) which you might be taking for your aggressive erosive osteoarthritis. These NSAIDs disrupt the protective mucosal barrier lining the inside the stomach, so the acid then reaches the stomach lining causing ulcer and pain. It's not your gallbladder. And the diarrhoes can be due to your celiac disease which has be aggeravated by your gastritis. I would start you on proton pump inhibitors like pantaprazole or rabeprazole. These will reduce the acid production by the stomach and will help in healing of the ulcers. Also you will need preprobiotics to control your diarrhea, as they will restore healthy microbial flora in your gut. For rapid relief of pain you can also take an antacid with an anesthetic combination. But these are prescription drugs and you need to see your local doctor for it and their dosage. Hope I have answered to all your queries. If you have further queries, I will be glad to answer them. Get Well Soon! Dr. Ashish Verma

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