Brief Answer:
Get him evaluated by a physician to alleviate the anxiety

Detailed Answer:
Hello

Thanks for the query

There can be so many causes of early morning dizziness.

The common causes are low blood sugar(more in morning due to prolonged overnight fast),orthostatic hypotension(low blood pressure detected in upright position after a prolonged recumbent position),low hemoglobin(early symptom of morning dizziness).

The uncommon causes are cardiac cause(any cause causing decreased cardiac output).

In most of the cases it is only subjective feeling(may be due to improper sleep) without any pathology.Although I won't get overly worried,but as there is history of repeated early morning dizziness I would like to get him evaluated by a physician to alleviate the anxiety and for early detection of the cause if any.

Please do ask if you have any more query.
Regards

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