[Verified Answer]: A nurse is caring for an 81-year-old…

A nurse is caring for an 81-year-old client in a long-term care facility who takes nine different medications each day. The client has a recent diagnosis of seizure disorder and has begun treatment with phenytoin (Dilantin), a highly protein-bound drug. After 1 month of Dilantin therapy, the client is still extremely drowsy and sluggish. The nurse determines that the prolonged adverse effect is likely due to: polypharmacy decreasing the number of available protein-binding sites. increased efficiency of the blood-brain barrier. an increase in creatinine to be filtered. the normally low protein-binding properties of Dilantin.