Dose adjustment is important as a slight change in the dose of Phenytoin can lead to a significant increase in its serum concentration. This can cause acute toxicity. Therapeutic drug monitoring is required to aid in the adjustment of drug dosage. If a patient is already consuming Phenytoin, then a top-up loading dose is needed. This can be calculated by determining the current concentration of Phenytoin in the plasma by using the formula.
Dose adjustment is important as a slight change in the dose of Phenytoin can lead to a significant increase in its serum concentration. This can cause acute toxicity. Therapeutic drug monitoring is required to aid in the adjustment of drug dosage. If a patient is already consuming Phenytoin, then a top-up loading dose is needed. This can be calculated by determining the current concentration of Phenytoin in the plasma by using the formula.
Top-Up Phenytoin = (20 - (measured concentration (mg/L)) x 0.7 x weight (kg) Sodium Dose