Corrected Magnesium Calculator

Calculate corrected magnesium level for patients with hypoalbuminemia using the Kroll-Elin formula

Calculate Corrected Magnesium

Laboratory serum magnesium measurement

Serum albumin concentration

Corrected Magnesium Results

0.00
mEq/L
0.00
mg/dL
0.00
mmol/L

Formula used: Corrected Mg = Serum Mg + 0.005 × (40 - Albumin)

Input values: Mg: 0.00 mEq/L, Albumin: 0.0 g/L

Correction amount: 0.000 mEq/L

Normal range: 1.3-2.1 mEq/L (0.65-1.25 mmol/L)

Clinical Significance

Example Calculation

Patient with Hypoalbuminemia

Clinical scenario: 65-year-old patient with liver cirrhosis

Serum magnesium: 1.2 mEq/L (appears low)

Serum albumin: 25 g/L (hypoalbuminemia)

Note: Low albumin may cause falsely low magnesium

Corrected Calculation

Corrected Mg = 1.2 + 0.005 × (40 - 25)

Corrected Mg = 1.2 + 0.005 × 15

Corrected Mg = 1.2 + 0.075

Corrected Mg = 1.275 mEq/L (Normal range)

Result: No magnesium supplementation needed

Magnesium Functions

Enzyme Cofactor

Essential for 300+ enzymatic reactions

💓

Cardiac Function

Enables cardiomyocyte contraction

🩸

Blood Clotting

Stabilizes platelets in blood

⚠️ Medical Disclaimer

This calculator is for educational purposes only and should not replace professional medical judgment.

Always consult with a qualified healthcare provider for proper interpretation of laboratory results and treatment decisions.

Clinical correlation is essential for accurate patient assessment.

Understanding Corrected Magnesium

What is Corrected Magnesium?

Corrected magnesium accounts for low albumin levels that can cause falsely low serum magnesium readings. Since 30% of serum magnesium is bound to proteins (mainly albumin), hypoalbuminemia reduces total magnesium levels while free, biologically active magnesium may remain normal.

Why Correction is Necessary

  • Only free magnesium (70%) is biologically active
  • Bound magnesium (30%) depends on albumin levels
  • Prevents unnecessary magnesium supplementation
  • Provides accurate assessment of magnesium status

Kroll-Elin Formula

Corrected Mg = Serum Mg + 0.005 × (40 - Albumin)

  • Corrected Mg: Albumin-corrected magnesium level
  • Serum Mg: Laboratory measured magnesium
  • 40: Reference albumin level (g/L)
  • 0.005: Correction factor

When to Use

  • Albumin < 35 g/L (hypoalbuminemia)
  • Liver disease or cirrhosis
  • Nephrotic syndrome
  • Malnutrition or severe inflammation

Hypomagnesemia Symptoms

Electrolyte Abnormalities

  • • Hypocalcemia (resistant to treatment)
  • • Hypokalemia (resistant to treatment)
  • • Hypophosphatemia

Clinical Manifestations

  • • Heart arrhythmias and ECG changes
  • • Muscle weakness and tremor
  • • Tetany (involuntary muscle contractions)