phosphorus (p) (serum)
ElectrolyteBlood sampleResults 24 hrsNo fasting
Phosphorus (P) (Serum)
Phosphorus is a mineral that works with calcium to support bones, energy, and many body processes. This test measures phosphorus in your blood, often checked alongside calcium and kidney markers.
Sample
Blood
Results
24 hrs
Fasting
Not required
Follow-up
Optional add-on
What this test detects
Phosphorus
Enzymatic colorimetry · serum
Quantitative · mg/dL
When to get this test
Bone and mineral health
Helps assess bone metabolism and the balance between phosphorus and calcium.
Kidney function
The kidneys regulate phosphorus, so levels are useful in monitoring kidney health.
Parathyroid and vitamin D
Supports evaluation of parathyroid and vitamin D-related conditions affecting minerals.
How to prepare
01
No special preparation needed.
Common questions
Why check phosphorus with calcium?
Phosphorus and calcium are closely linked and regulated together. Checking both gives a clearer view of bone and mineral balance.
What can raise phosphorus levels?
Reduced kidney function is a common reason for high phosphorus, since the kidneys help clear it. Certain conditions and supplements can also play a role.