Brief Answer:
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Detailed Answer:
I read your question carefully and I understand your concern.

Judging from your description your husband manifests what is called orthostatic hypotension, an excessive drop in blood pressure when changing position from supine to standing.

Orthostatic hypotension is a manifestation which may be due to different causes, so naturally the first step in its evaluation is searching for the cause. There are neurological causes (such as multiple system atrophy, pure autonomic failure, parkinson's disease etc); hormonal related causes such as diabetes, Addison's disease, thyroid dysfunction; heart conditions etc. Certain medications can also cause orthostatic medication.

So first the list of medications (if any) is to be reviewed. If no medications which can be at fault are found then other non-neurogenic causes are to be looked for, that is through a physical exam from your doctor for signs of the heart or endocrine conditions I mentioned, as well as excluding dehydration. Some blood tests may be necessary for endocrine disorders.
If no such causes are found then neurological causes should be considered. A neurological consult to check for signs of Parkinson's, multiple system atrophy, peripheral neuropathy etc is necessary. These conditions manifest usually through subtle signs that is why usually a neurological consult is necessary not only of the family doctor.
Regarding management of course if a cause is found it should be addressed. Other measures include increasing salt and fluid intake, standing up gradually, elevating the head of the bed, using elastic compression stocking.
If those are not enough medication which may be considered includes fludrocortisone, midodrine or droxidopa.

I remain at your disposal for other questions.

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