Thanks for your question.
The burning pain in the legs is due to some abnormality in the nerve pathway which is causing this abnormal sensation. This could be due to a condition in the back from where the nerves begin, or a disease of the nerves itself such as due to Vitamin B12 deficiency or longstanding uncontrolled diabetes.
If omeprazole is not working for the burning pain in the abdomen, the cause for your abdominal pain is unlikely to be due to increased acid secretion, and other causes need to investigated by your doctor. That is the reason they have sent you for the bowel check.
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