Understanding Your Lab Results
Knowledge is power. Understanding your lab values helps you advocate for yourself and have informed conversations with your healthcare team.
Important
Lab reference ranges can vary between laboratories. Always discuss your results with your endocrinologist or healthcare provider. The ranges listed here are general guidelines. Your doctor knows your individual situation best.
Key Lab Values for Hypoparathyroidism
These are the most important labs your endocrinologist should be monitoring. Bring this list to your next appointment.
Total Calcium (Serum)
Normal Range
8.5 – 10.5 mg/dL
In Hypopara
Often below 8.5 mg/dL
The most basic calcium test. In hypopara, this is typically low. However, it can be affected by albumin levels, so corrected calcium is often more accurate.
Ionized Calcium
Normal Range
4.5 – 5.3 mg/dL (1.12 – 1.32 mmol/L)
In Hypopara
Often below 4.5 mg/dL
Measures the 'free' calcium in your blood — the calcium your body can actually use. This is the most accurate calcium measurement and is not affected by albumin levels.
Parathyroid Hormone (PTH)
Normal Range
15 – 65 pg/mL
In Hypopara
Low or undetectable
This is the defining lab for hypoparathyroidism. Low or absent PTH is what causes the condition. If your PTH is low AND your calcium is low, that confirms hypopara.
Phosphorus
Normal Range
2.5 – 4.5 mg/dL
In Hypopara
Often elevated (above 4.5 mg/dL)
PTH normally helps the kidneys excrete phosphorus. Without enough PTH, phosphorus builds up. High phosphorus can worsen symptoms and contribute to calcifications.
Magnesium
Normal Range
1.7 – 2.2 mg/dL
In Hypopara
Can be low
Magnesium is essential for PTH secretion and calcium regulation. Low magnesium can worsen hypopara symptoms and make calcium harder to absorb. Often overlooked but critically important.
25-Hydroxyvitamin D
Normal Range
30 – 100 ng/mL
In Hypopara
May be low or normal
This measures your vitamin D stores. Adequate vitamin D is needed for calcium absorption. Many hypopara patients are deficient and need supplementation.
1,25-Dihydroxyvitamin D (Calcitriol)
Normal Range
20 – 76 pg/mL
In Hypopara
Often low without supplementation
This is the ACTIVE form of vitamin D. PTH is needed to convert vitamin D to its active form. Without PTH, your body can't make enough calcitriol — which is why hypopara patients take calcitriol as a medication.
Albumin
Normal Range
3.5 – 5.5 g/dL
In Hypopara
Usually normal (but affects calcium reading)
Albumin is a protein that calcium binds to. Low albumin makes total calcium appear falsely low. That's why we calculate 'corrected calcium' — adjusting for albumin levels.
24-Hour Urine Calcium
Normal Range
100 – 300 mg/24 hours
In Hypopara
Should be monitored regularly
Measures how much calcium your kidneys are excreting. Too much calcium in the urine increases kidney stone risk. This is especially important for hypopara patients on high-dose calcium supplements.
Creatinine / BUN
Normal Range
Creatinine: 0.6 – 1.2 mg/dL
In Hypopara
Monitor for kidney function
Kidney function tests are essential because long-term hypopara and high calcium supplementation can affect the kidneys. Kidney calcifications and stones are a known complication.
Doctor Print-Out
Print this summary and bring it to your next endocrinology appointment. It can help ensure all the right labs are being ordered.
Recommended Lab Panel for Hypoparathyroidism
1. Total Calcium (Serum)
2. Ionized Calcium
3. Parathyroid Hormone (PTH) — Intact
4. Phosphorus
5. Magnesium
6. 25-Hydroxyvitamin D
7. 1,25-Dihydroxyvitamin D (Calcitriol)
8. Albumin
9. 24-Hour Urine Calcium
10. Creatinine / BUN (Kidney Function)
11. Complete Metabolic Panel (CMP)
Patient: _________________________ Date: _____________
Track Your Results Over Time
Use our Calcium Calculator and Patient Portal to track your corrected calcium levels over time. Knowledge is your best tool.
Medical Disclaimer: The information provided on this page is for educational and informational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Lab reference ranges may vary between laboratories. Always consult your physician or qualified healthcare provider for interpretation of your lab results and any questions regarding your medical condition. Bari Gordon Vapnek is a patient advocate, not a medical professional.