Question

A client with a history of seizures is taking phenytoin for seizure control. The client arrives at the health care clinic, and a serum phenytoin drug level is drawn. The laboratory calls the nurse and reports a result of 10 mcg/mL. Which interpretation should the nurse make of this value?

A. Below therapeutic range
B. Within the therapeutic range
C. Above therapeutic range
D. Critical value, notify the healthcare provider

Answer 1

The serum phenytoin drug level of 10 mcg/mL is within the therapeutic range for seizure control, which is typically 10-20 mcg/mL. This level helps to avoid drug toxicity while effectively preventing seizures.

Step-by-step explanation:

A serum phenytoin drug level of 10 mcg/mL should be interpreted as within the therapeutic range for seizure control. The therapeutic range for phenytoin is typically 10-20 mcg/mL, and this range is considered ideal for preventing seizures without causing significant drug toxicity. Monitoring levels is important due to the narrow therapeutic range and significant inter-individual variability in systemic exposure. Adjustments to the dose may be necessary based on levels drawn from plasma or serum to tailor the treatment to the patient, taking into account the clear relationship between blood exposure and clinical effect. Therefore, there is no need for immediate concern or to notify the healthcare provider as it is not a critical value.