Calcium with Phosphate and Parathyroid Hormone (PTH) Profile (Serum)

Why This Test Is Done

Doctors may order this test to evaluate symptoms like bone pain, frequent fractures, kidney issues, or abnormal calcium levels. It’s also used in monitoring conditions like osteoporosis, hyperparathyroidism, or kidney disease. Sometimes, it’s part of routine check-ups for patients at higher risk of calcium-related problems.

What to Expect Before the Test

No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if calcium is measured separately. Wear loose clothing and avoid tight sleeves for easy vein access. Bring any medications you’re taking, as some (like calcium supplements) may affect results.

What Happens During the Test

A healthcare provider will draw blood from a vein in your arm using a small needle. You may feel a slight pinch, but it’s over quickly. The blood sample is sent to a lab for analysis of calcium, phosphate, and PTH levels.

What the Results Mean

Results are compared to standard ranges, but exact values can vary by lab. Low calcium or high phosphate may signal conditions like vitamin D deficiency or kidney problems, while high calcium or low PTH could indicate hyperparathyroidism or bone disorders. Your doctor will interpret results in the context of your health history and symptoms.