Brief Answer:
Impossible to say what causes pain without examini

Detailed Answer:
Hello,

Thanks for the query.

I am sorry for your mother's condition, I can understand the suffering you and she must be going through.

There is no medical condition that causes such typical pain but only at a fixed time every night.

The pain you describe is usually seen with pancreatitis perforation of the stomach etc., but that pain is constant and does never occur at one particular time of the day.

And without actually being able to examine your mother, I am sorry to say, it is impossible to make a diagnosis.

And these conditions are easily diagnosed on clinical examination and simple investigations such as an X-ray, Ultrasound scan, and some blood tests, and a CT scan at the most.

What I mean to say is, if there is a pain then it should be very straight forward to find the exact cause for such pain unless it is psychological.

And pain that is not relieved with pain medicines is unlikely to be due to any organic disease.

If you would still want to find the reason for pain, I would suggest these following tests.,

1. Serum Lipase and Amylase levels.
2. Renal Doppler.
3. X-ray of the abdomen.
4. Doppler or angiogram of the abdominal blood vessels to see if there is any ischemia.
5. CT/MRI scan of the abdomen and pelvis.
6. Upper GI endoscopy.

I suspect all these investigations have been performed.

Please talk to her psychiatrist again and see if anything more can be done to treat her depression.

I sincerely hope this helps you understand the issue. You are welcome to ask me anything.

All the best.

Kind regards.

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