Brief Answer:
he needs immediate medical attention and hospitalization right away..

Detailed Answer:
Hello XXXXX, Welcome to HCM,
I've gone through your query and understand your concern,

Please note that Serum Calcium level of 16 is not sustainable for human body and it's quite severe, what we call as hypercalcemia crisis..

He needs immediate hospitalization and thorough investigation as well as immediate emergency medical management..

All those symptoms you've mentioned are primarily due to the hypercalcemia only..it's quite severe at present and has to be managed without any further delay, at such high level it can even cause seizure and several other organ damage, since he's already dizzy, please don't try to give anything orally and take him to you nearest Hospital's ER (Emergency) for immediate management..

Please take him to your nearby Hospital's ER for immediate management followed by in patient admission..the first thing to do right away is fast volume replacement (I.V with 0.9%Saline initially) along with complete metabolic check-up (Arterial Blood Gas, CBC, LFT, KFT, ELECTROLYTES, 12 lead ECG, RBS, Thyroid function test, Coagulation profile etc.)..

Serial calcium monitoring will be required along with I.V. therapy (initially volume replacement followed by short course of diuretics therapy, with injectable Calcitonin therapy and if still fails to correct then emergency hemodialysis will be required)..along with this Endocrinological assessment will be required to find out the cause..

Please don't delay anymore..

Best Wishes

Let me know how he stays in the due course..

Kind Regards

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