Calcium · high result
What does a high Calcium mean?
Short answer
High calcium (hypercalcemia) in an outpatient is most often primary hyperparathyroidism — an overactive parathyroid gland — followed by medications (thiazides, lithium, excess vitamin D or calcium supplements). Cancer-related hypercalcemia is the main concern in someone who is unwell. A high calcium should be repeated with albumin (or ionized calcium) and a PTH level.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When does this result need same-day care?
- Calcium above about 13 mg/dL, or any elevation with confusion, severe vomiting or dehydration — same-day care
What is the normal range for Calcium?
- age 18+: 8.60 – 10.3 mg/dL
Often reflects parathyroid issues, certain cancers, or excess vitamin D.
Full reference table, citations and testing options: Calcium biomarker page.
What are the common causes of high Calcium?
- Primary hyperparathyroidism
- Thiazide diuretics, lithium, excess vitamin D or calcium supplements
- Dehydration (mild, with a high albumin)
- Cancer: bone involvement or hormone-producing tumors
- Granulomatous disease (sarcoidosis), hyperthyroidism, prolonged immobilization
What symptoms go with high Calcium?
- Often none when mild
- Thirst, frequent urination, constipation
- Fatigue, bone aches, kidney stones
- Confusion when high
What do clinicians usually check next?
- Repeat with albumin or ionized calcium
- Intact PTH — high or 'inappropriately normal' points to the parathyroid
- 25-hydroxyvitamin D, phosphorus, kidney function
- Medication and supplement review
Follow-up tests available at TestWell: PTH (Parathyroid Hormone) ($59.99), Phosphorus ($18.99).
How do you recheck Calcium?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Basic Metabolic Panel | Test · 8 biomarkers | $20.99 | Yes | 1–3 business days |
Common questions
What is the most common cause of high calcium?
In otherwise well people, primary hyperparathyroidism. PTH is the test that identifies it.
Sources
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.