Brief Answer:
?? Orthostatic or postural hypotension

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence ma'am, and shall surely help you with the information you are looking for.

The symptom described by you is related to a condition called orthostatic hypotension (also called orthostasis). In this condition, there is a drop of blood pressure with change in posture especially when a person sits up or stands from a supine position. Symptoms include feeling dizzy or lightheaded on change of posture or may be even fainting.

Causes are various ma'am, but let me list the most common and plausible ones out for you:
-Cardiac conditions
-Hypoglycemia
-Thyroid abnormalities
-Adrenal insufficiency
-Dehydration
-Nervous conditions
-Improper management of blood pressure
and a few others.

I would request you to schedule an appointment with your doctor to check on your blood pressure, and if required make changes to your treatment regimen. Also, please request your doctor to check on your blood sugar levels and also rule out other possible causes for your presentation ma'am. You will require an elaborate general evaluation.

I hope you find my response both helpful and informative ma'am. Please feel free to write back to me for any further clarifications, I would be more than happy to help you.

Best wishes.

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