A client was prescribed phenytoin (100 mg PO 3 times a day) a month ago. Today, the client has a serum phenytoin level of 32 mcg/mL (127 mcmol/L). The nurse notifies the health care provider and expects which prescription?

Question

A client was prescribed phenytoin (100 mg PO 3 times a day) a month ago.  Today, the client has a serum phenytoin level of 32 mcg/mL (127 mcmol/L).  The nurse notifies the health care provider and expects which prescription?

Quizplus · Accepted Answer

Phenytoin (Dilantin) is an anticonvulsant drug used to treat generalized tonic-clonic seizures. The therapeutic serum phenytoin range is 10-20 mcg/mL (40-79 mcmol/L). In the presence of an elevated phenytoin level (32 mcg/mL [127 mcmol/L]), the nurse anticipates that the health care provider will prescribe a decreased daily dose (Option B). The nurse should continue to monitor for signs of toxicity, typically presenting as neurological manifestations (eg, ataxia, nystagmus, slurred speech, decreased mentation). (Options A and C) The serum phenytoin level is above the therapeutic level, so administering the prescribed dose or increasing the dose can further increase the risk for drug-induced toxicity. (Option D) Repeating the serum phenytoin level in 2 hours will not result in a significant change because the average half-life of the drug is 22 hours. Educational objective: Phenytoin (Dilantin) is used to treat generalized tonic-clonic seizures. Common symptoms of phenytoin toxicity involve the central nervous system (eg, nystagmus, ataxia, slurred speech, decreased mentation) and can occur when serum phenytoin levels exceed the therapeutic range (10-20 mcg/mL [40-79 mcmol/L]).

A Client Was Prescribed Phenytoin (100 Mg PO 3 Times