RT Book, Section A1 Anker, Naomi B. A1 Cho, Kerry C. A2 Papadakis, Maxine A. A2 McPhee, Stephen J. A2 Rabow, Michael W. SR Print(0) ID 1166170150 T1 Disorders of Calcium Concentration T2 Current Medical Diagnosis and Treatment 2020 YR 2020 FD 2020 PB McGraw-Hill Education PP New York, NY SN 9781260455281 LK accessmedicine.mhmedical.com/content.aspx?aid=1166170150 RD 2022/05/20 AB The normal total plasma (or serum) calcium concentration is 8.5–10.5 mg/dL (or 2.1–2.6 mmol/L). Ionized calcium (normal: 4.6–5.3 mg/dL [or 1.15–1.32 mmol/L]) is physiologically active and necessary for muscle contraction and nerve function.