Magnesium Replacement: 2 Grams IV Replaces Approximately 16 mEq (8 mmol) of Elemental Magnesium
A 2-gram intravenous dose of magnesium sulfate provides approximately 16 mEq (8 mmol) of elemental magnesium, which is the standard replacement dose for moderate magnesium deficiency in adults.
Understanding Magnesium Dosing Conversions
The question appears to ask about magnesium replacement, though the evidence provided does not directly address this specific conversion. Using general medical knowledge:
- 2 grams of magnesium sulfate (MgSO₄) contains approximately 16 mEq (8 mmol) of elemental magnesium
- Magnesium sulfate is 49.3% elemental magnesium by weight
- 2 g MgSO₄ = 2000 mg × 0.493 = 986 mg elemental magnesium
- 986 mg ÷ 12.15 mg/mmol = approximately 8 mmol = 16 mEq
Clinical Context for IV Magnesium Replacement
For symptomatic hypomagnesemia or severe deficiency (Mg <1.0 mg/dL), administer 2 g magnesium sulfate IV over 15-30 minutes
- This provides rapid correction for patients with cardiac arrhythmias, seizures, or severe symptoms
- Slower infusion rates (over 2 hours) reduce the risk of hypotension and flushing
For moderate hypomagnesemia (Mg 1.0-1.5 mg/dL), give 1-2 g magnesium sulfate IV over 1-2 hours
- Can be repeated every 6-8 hours based on serum levels
- Total daily dose typically should not exceed 8-10 g without close monitoring
Important Safety Considerations
Monitor for magnesium toxicity when administering IV magnesium, particularly in patients with renal impairment
- Signs include hypotension, bradycardia, respiratory depression, and loss of deep tendon reflexes
- Check serum magnesium levels 2-4 hours after infusion
Administer magnesium sulfate slowly to avoid adverse effects
- Rapid bolus can cause severe hypotension, cardiac arrhythmias, and respiratory depression
- Maximum safe infusion rate is generally 1-2 g/hour for non-emergent situations
Renal function must be assessed before repeated dosing
- Patients with creatinine clearance <30 mL/min require dose reduction (typically 50% of standard dose)
- Risk of hypermagnesemia increases significantly with impaired renal excretion