What is the accepted therapeutic serum magnesium concentration range for prevention of eclamptic seizures?

• A 12 to 15 mg/dL
• B 9 to 12 mg/dL
• C 4.8 to 8.4 mg/dL ✓
• D 2 to 4 mg/dL

Explanation

The therapeutic range for seizure prophylaxis is approximately 4.8 to 8.4 mg/dL, equivalent to roughly 4 to 7 mEq/L. Loss of deep tendon reflexes occurs around 9 to 12 mg/dL, respiratory paralysis near 12 to 18 mg/dL, and cardiac arrest above 24 mg/dL. Recognizing these thresholds explains why reflex loss is the earliest reliable clinical sign of toxicity.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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