Brief Answer:
vitamin d raises calcium

Detailed Answer:
HI, thanks for using healthcare magic

Vitamin D is one of the hormones/vitamins that is involved in controlling calcium levels in the body. It helps the intestines absorb or take in more calcium from food/drink.
This is one of its main actions

Taking vitamin D will raise your calcium further since it will make sure that more calcium is absorbed into the body.

Your doctors would need to find out if there is any other cause of the high calcium since high levels can sometimes occur in dangerous conditions eg rarely cancer, this has to be ruled out

Additional blood tests like phosphorus, creatinine (to check kidney function), parathyroid hormone (another hormone that helps raise calcium), complete blood count.
These would help to pin point the cause

I hope this helps, feel free to ask any other questions

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