Brief Answer:
Following causes to feeling dizzy when standing...

Detailed Answer:
Hi there,

I am sorry for the situation you are in. Based on what you are saying, my thoughts go for possible:
- problems with your blood vessels: should run Doppler ultrasound of neck and peripheral blood vessels
- Menier's syndrome: should run an audiogram and check the inner ear (TILT test)
- Autoimmune diseases: Raynald's syndrome, etc.

I also advise to run: ECG, cardiac echo, Holter monitoring, monitor your blood pressure to rule out heart problems.

Depending on the tests results, specific treatment will be prescribed.

Meanwhile, I advise to:
- stand up slowly (not too quick)
- keep hydrated (drink more water)
- raise your feet where-ever possible
- do not stay in standing position for long period

Hope it was of help! If anything unclear, do not hesitate to write me back!
Dr.Benard

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