What should you know about high blood calcium low vitamin D?

Calcium and vitamin D are related to bone health, but one blood result does not explain the whole picture. A clinician may check whether calcium remains high, review albumin and kidney function, and assess parathyroid hormone, supplements and medicines. Low vitamin D can coexist with high calcium for more than one reason.

Possible symptoms include thirst, constipation, nausea, tiredness, [generalised weakness](/symptoms/generalised-weakness/) or [joint pain](/symptoms/joint-pain/), although some people have no symptoms. Bone discomfort or a [stress fracture](/conditions/stress-fracture/) deserves specific assessment.

Book a review with the clinician who arranged the blood tests. Bring a list of vitamin D, calcium, antacid and other supplements, plus prescribed medicines and details of kidney or digestive problems. Do not start high-dose vitamin D or calcium until the plan is clear; excess supplementation can raise calcium further.

Follow the advised repeat-test schedule and maintain ordinary fluid intake unless you have been given a restriction. Mention [fatigue](/symptoms/fatigue/), low mood or recurrent infections, even if they seem unrelated.

Seek urgent care for repeated vomiting, marked confusion, severe weakness, fainting, an inability to keep fluids down, severe abdominal pain or a major change in urination. These symptoms can indicate a significant calcium disturbance or another acute problem.

Ask whether the calcium result is confirmed, which tests will look for its cause, whether supplements should pause, and how vitamin D can be replaced safely. Discuss kidney function, bone health, digestive symptoms and any family history of calcium disorders.