What is the normal range for serum magnesium (Mg2+)?

What is the normal range for serum magnesium (Mg2+)?

• A. 0.8–1.2 mg/dL
• B. 1.7–2.2 mg/dL
• C. 2.5–3.5 mg/dL
• D. 3.0–3.5 mg/dL

Answer: (B)

Normal serum magnesium is about 1.7 to 2.2 mg/dL. This range is the standard reference for adults and reflects a balance maintained by intestinal absorption, renal excretion, and cellular distribution. Values below this range indicate hypomagnesemia, which can lead to symptoms like muscle cramps, tremors, seizures, and potential cardiac arrhythmias. Values above this range indicate hypermagnesemia, which can cause decreased reflexes, hypotension, and respiratory or cardiac issues, especially in kidney failure. The given range of 1.7–2.2 mg/dL matches the typical normal reference, making it the best choice. The other ranges are either too low or too high to be considered normal.

Normal serum magnesium is about 1.7 to 2.2 mg/dL. This range is the standard reference for adults and reflects a balance maintained by intestinal absorption, renal excretion, and cellular distribution. Values below this range indicate hypomagnesemia, which can lead to symptoms like muscle cramps, tremors, seizures, and potential cardiac arrhythmias. Values above this range indicate hypermagnesemia, which can cause decreased reflexes, hypotension, and respiratory or cardiac issues, especially in kidney failure. The given range of 1.7–2.2 mg/dL matches the typical normal reference, making it the best choice. The other ranges are either too low or too high to be considered normal.