Brief Answer:
Please give details and post actual reports if done

Detailed Answer:
Hi.
Thanks for your query.
To recapitulate: Female/53 - steady achy pain - middle of stomach - hurts worse in the morning - deep breathing is painful - visited a Doctor - prescribed oxycodone - does not want to take - knows it is not acid reflux...

Please give additional information for me to assist you better:
- Since when is the pain present?
- Please specify the exact area of pain?
- Is it under the ribs?
- Any associated symptoms of nausea, bloating, vomiting, change in bowel habits?
- What was the opinion of your Doctor and is only Oxycodone prescribed?
- Any investigations?

With the short history you have provided this looks to be one of the following:
- Costochondritis as the pain increases on deep breathing.
- Or can be related to some internal organ inflammation like gall bladder or so wherein there is increase in pain during deep breathing.

Please give additional information so that we can discuss further.

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