Brief Answer: Probably from the stomach.... Detailed Answer: Hi, Normal human have the liver placed in the right upper quadrant overlapped by the right lower ribs. Gall bladder is present within this vicinity (imagine two lines intersecting - one running perpendicularly through mid clavicle/collar bone and the other horizontally at the lower end of ribs - the intersection is where gall bladder would be closely related). Stomach lies just under the sternum (breast bone); this area is referred to as epigastric region. Spleen at the left upper quadrant overlapped by left lower ribs. Kidney is closely related to the back on both sides of lower back. Appendix would be at the right lower quadrant above the pelvic bones. Besides these organ the digestive tract consisting of small and large intestines are widely spread across all parts of abdomen. Accordingly the dull pain in the midsection slightly towards the right may be from the stomach. Since the pain occurred following drugs, perhaps it may due to drug induced gastritis. It should respond very well to proton pump inhibitor drugs or antacids. Hope this helps. Let me know if you need clarifications. Regards

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