What formula corrects phenytoin for hypoalbuminemia?

Sheiner-Tozer: Corrected = Measured / ((0.2 × albumin) + 0.1) for patients with normal renal function. For dialysis patients: Corrected = Measured / ((0.1 × albumin) + 0.1). Normal albumin = 4.4 g/dL.

When must phenytoin be corrected for albumin?

Albumin correction is essential when albumin <3.5 g/dL — common in critical illness, malnutrition, hepatic failure, pregnancy, nephrotic syndrome, and burns — where total level significantly underestimates bound drug and overestimates free drug effect.

Phenytoin Free Level Correction for Hypoalbuminemia

Calculate corrected (adjusted) phenytoin level for hypoalbuminemia or renal failure using the Sheiner-Tozer equation to avoid under- or overdosing based on misleading total phenytoin concentrations.

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Phenytoin Free Level Correction for Hypoalbuminemia

Frequently Asked Questions

What formula corrects phenytoin for hypoalbuminemia?

When must phenytoin be corrected for albumin?