Normal range 4.6-5.3 mg/dL (1.15-1.33 mmol/L SI). Specimen: Serum or whole blood.
Also known as: free calcium, iCal.
4.6-5.3 mg/dLCritical value: read below
Reference range
Conventionalmg/dL
4.65.3
SImmol/L
1.151.33
Combined adult band. LabVals does not publish separate men's, women's, or pediatric ranges for Calcium, Ionized; those can be narrower than the band shown.
Calcium, Ionized reference range, specimen, and conversion details
Convert any Calcium, Ionized result between units on the unit converter.
What is the normal range for Calcium, Ionized?
The standard teaching reference range for Calcium, Ionized is 4.6-5.3 mg/dL in conventional units, or 1.15-1.33 mmol/L in SI units. This value is measured in serum or whole blood.
What is a critical Calcium, Ionized value?
For Calcium, Ionized, the commonly taught critical (panic) value is: < 3.2 or > 6.2 mg/dL. Critical results are reported to the provider immediately under your facility's policy.
Source: Adult reference values compiled from Pagana & Pagana, Mosby's Diagnostic and Laboratory Test Reference, and Fischbach & Dunning, A Manual of Laboratory and Diagnostic Tests. Reference ranges vary by laboratory, method, age, sex, and population - always use the range printed on the actual result.
The physiologically active fraction; unaffected by albumin, so preferred in critical illness.
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