Description
Why It’s Done
The Phosphorus Serum Test is commonly ordered to:
• Assess kidney function, as abnormal phosphorus levels can indicate kidney problems.
• Help diagnose and monitor conditions such as:
o Hyperphosphatemia (high phosphorus levels)
o Hypophosphatemia (low phosphorus levels)
o Osteomalacia or rickets (bone softening due to low phosphorus)
o Hyperparathyroidism (overactivity of the parathyroid glands)
• Evaluate bone health, especially in individuals with conditions like osteoporosis or kidney disease.
• Monitor the effects of phosphorus supplements or medications affecting phosphorus levels.
Preparation
• Fasting: Your doctor may recommend fasting for 8–12 hours before the test to get an accurate result, though fasting is not always required.
• Medications: Inform your doctor about any medications you are taking, as certain drugs (like antacids or diuretics) can affect phosphorus levels.
• Sample: A blood sample is taken from a vein in your arm


