Question 1

A patient with a seizure disorder is admitted to the hospital and has a partial convulsive episode shortly after arriving on the unit. The patient has been taking phenytoin (Dilantin) 100 mg three times daily and oxcarbazepine (Trileptal) 300 mg twice daily for several years. The patient's phenytoin level is 8.6 mcg/mL, and the oxcarbazepine level is 22 mcg/mL. The nurse contacts the provider to report these levels and the seizure. What will the nurse expect the provider to order?

Accepted Answer

This patient's phenytoin level is low; the therapeutic range is 10 to 20 mcg/mL. An increase in the phenytoin dose is necessary. The oxcarbazepine level is within the normal range of 3 to 40 mcg/mL, so changing the dose is not necessary. Extended-release phenytoin is absorbed more slowly and would not increase this patient's serum phenytoin level. The dosing of oxcarbazepine does not need to be changed.

Question 2

A nurse is discussing partial versus generalized seizures with a group of nursing students. Which statement by a student indicates understanding of the teaching?

Accepted Answer

Febrile seizures typically manifest as a tonic-clonic seizure of short duration and are a type of generalized seizure. Generalized seizures may be convulsive or nonconvulsive. Partial seizures may last longer than some types of generalized seizures. Patients with complex partial seizures and secondarily generalized seizures, which are types of partial seizures, may lose consciousness.

Question 3

A patient who has been taking phenobarbital for epilepsy begins taking valproic acid (Depakote) as adjunct therapy. The nurse notes that the patient is very drowsy. What will the nurse do?

Accepted Answer

Valproic acid competes with phenobarbital for drug-metabolizing enzymes and can increase plasma levels of phenobarbital by approximately 40%. When this combination is used, the dose of phenobarbital should be reduced. Increasing the dose of valproic acid would compound the problem. Patients taking phenobarbital alone experience sedation, which diminishes as tolerance develops. Liver toxicity is a rare adverse effect of valproic acid and is marked by symptoms of nausea, vomiting, and malaise, not drowsiness.

Question 4

A nurse is completing a discharge plan for a 24-year-old patient who will begin taking phenytoin. Which information is important to teach this patient?

Accepted Answer

Because antiepileptic drugs can harm a fetus, female patients of childbearing age should be counseled about the use of contraceptives, which may also have drug-to-drug interactions with the antiepileptic drugs. Patients should be counseled that withdrawal of a seizure medication should be done only with the advice of their prescriber and not just when a certain period of time has passed without seizures. Taking a seizure medication is not a guarantee that seizures will not occur; managing seizures often requires experimenting with several different medications. Patients should report side effects and, if they are serious, should discontinue a drug but only under the guidance of their prescriber.

Question 5

A patient is admitted to the hospital for a new onset seizure disorder, and the prescriber orders carbamazepine (Tegretol). The nurse reviewing the patient's medical history notes that the patient is taking warfarin. The nurse will contact the provider to discuss _____ dose.

Accepted Answer

Carbamazepine induces hepatic drug-metabolizing enzymes and can increase the rate at which it and other drugs are metabolized, including oral contraceptives and warfarin; therefore, patients taking any of these drugs would need an increased dose. Reducing the dose of either drug is not indicated. Increasing the dose of carbamazepine may be necessary but only after serum drug levels have been checked.

Question 6

A nurse counsels a patient who is to begin taking phenytoin (Dilantin) for epilepsy. Which statement by the patient indicates understanding of the teaching?

Accepted Answer

Gingival hyperplasia occurs in about 20% of patients who take phenytoin. It can be minimized with good oral hygiene, so patients should be encouraged to brush and floss regularly. Because small fluctuations in phenytoin levels can affect response, maintaining therapeutic levels is not easy. Patients should be cautioned against consuming alcohol while taking phenytoin. Rashes can be serious and should be reported immediately.

Question 7

A patient is to begin taking phenytoin (Dilantin) for seizures. The patient tells the nurse that she is taking oral contraceptives. What will the nurse tell the patient?

Accepted Answer

Because phenytoin can reduce the effects of oral contraceptive pills (OCPs) and because avoiding pregnancy is desirable when taking phenytoin, patients should be advised to increase the dose of oral contraceptives or use an alternative method of birth control. Increasing the patient's dose of phenytoin is not necessary; OCPs do not affect phenytoin levels. Phenytoin is linked to birth defects; OCPs have decreased effectiveness in patients treated with phenytoin, and the patient should be advised to increase the OCP dose or to use an alternative form of birth control. OCPs do not alter the effects of phenytoin.

Question 8

A patient shows loss of consciousness, jaw clenching, contraction and relaxation of muscle groups, and periods of cyanosis. The nurse correctly identifies this as which type of seizure?

Accepted Answer

Tonic-clonic seizures (or grand mal seizures) are considered generalized seizures and are manifested by a loss of consciousness, jaw clenching, muscle relaxation alternating with muscle contractions, and periods of cyanosis. Absence seizures (or petit mal seizures) are characterized by loss of consciousness for a brief period and usually involve eye blinking and staring into space. Myoclonic seizures consist of sudden contractions that may be limited to one limb or may involve the entire body. Atonic seizures are characterized by sudden loss of muscle tone.

Question 9

A patient who is taking oral contraceptives begins taking valproic acid (Depakote) for seizures. After a week of therapy with valproic acid, the patient tells the nurse that she is experiencing nausea. What will the nurse do?

Accepted Answer

Gastrointestinal effects, including nausea, vomiting, and indigestion, are common with valproic acid and can be minimized by taking the drug with food or using an enteric-coated product. Hyperammonemia can occur when valproic acid is combined with topiramate. Signs of pregnancy usually do not occur within a week, so this is less likely. Hepatotoxicity is a rare adverse effect.

Question 10

A nurse is providing teaching to a patient newly diagnosed with partial seizures who will begin taking oxcarbazepine (Trileptal). The patient also takes furosemide (Lasix) and digoxin (Lanoxin). Which statement by the patient indicates understanding of the teaching?

Accepted Answer

Oxcarbazepine can cause clinically significant hyponatremia in 2.5% of patients. If oxcarbazepine is combined with other drugs that reduce sodium, the patient should be monitored. Signs of hyponatremia include nausea, drowsiness, confusion, and headache, and patients should be taught to report these symptoms. Increasing the dose of oxcarbazepine is not indicated. Rashes can indicate a serious drug reaction, and providers should be notified so that the oxcarbazepine can be withdrawn. Salt substitutes would compound the problem of hyponatremia.

Question 11

A nurse is caring for a patient who has been taking an antiepileptic drug for several weeks. The nurse asks the patient if the therapy is effective. The patient reports little change in seizure frequency. What will the nurse do?

Accepted Answer

If medication therapy is not effective, it is important to measure serum drug levels of the medication to determine whether therapeutic levels have been reached and to help monitor patient compliance. Patients should be asked at the beginning of therapy to keep a seizure frequency chart to help deepen their involvement in therapy; asking for historical information is not helpful. Until it is determined that the patient is not complying, the nurse should not reinforce the need to take the medication. Until the drug level is known, increasing the dose is not indicated.

Question 12

A nurse provides teaching for a patient with a newly diagnosed partial complex seizure disorder who is about to begin therapy with antiepileptic drugs (AEDs). Which statement by the patient indicates understanding of the teaching?

Accepted Answer

Even with an accurate diagnosis of seizures, many patients have to try more than one AED to find a drug that is both effective and well tolerated. Unless patients are being treated for absence seizures, which occur frequently, monitoring of the clinical outcome is not sufficient for determining effectiveness, because patients with convulsive seizures often have long seizure-free periods. Serious side effects may occur, but withdrawing a drug precipitously can induce seizures. Not all patients have seizure control with therapeutic drug levels, because not all medications work for all patients.

Question 13

A child who receives valproic acid (Depakote) begins taking lamotrigine (Lamictal) because of an increase in the number of seizures. The nurse will observe this child closely for which symptom?

Accepted Answer

Lamotrigine can cause life-threatening rashes, such as Stevens-Johnson syndrome and toxic epidermal necrolysis, and this risk increases with concurrent use of valproic acid. Angioedema is an adverse effect associated with pregabalin. Hypohidrosis and psychosis are associated with topiramate.

Question 14

A nurse is assessing a patient who becomes motionless and seems to stare at the wall and then experiences about 60 seconds of lip smacking and hand wringing. What should the nurse do?

Accepted Answer

This patient showed signs of a complex partial seizure, characterized by impaired consciousness beginning with a period of motionlessness with a fixed gaze, followed by a period of automatism. The entire episode generally lasts 45 to 90 seconds. Absence seizures are characterized by loss of consciousness for a brief period (about 10 to 30 seconds) and may involve mild, symmetric motor activity or no motor signs. A grand mal seizure is characterized by jaw clenching and rigidity followed by alternating muscle relaxation and contraction and then periods of cyanosis, all with a loss of consciousness. Status epilepticus is a seizure that persists for 30 minutes or longer.

Question 15

A child is diagnosed with absence seizures, and the prescriber orders ethosuximide (Zarontin). When teaching the child's parents about dosage adjustments for this drug, the nurse will stress the importance of:

Accepted Answer

Measurements of plasma drug levels are less important than observation of seizure activity for determining effective dosages for absence seizures, because this type of seizure is characterized by as many as several hundred occurrences a day. Keeping a chart of seizure activity is the best way to monitor drug effectiveness when treating absence seizures. Frequent drug level monitoring is important when side effects occur to ensure that drug toxicity is not occurring. Learning about the disorder is an important part of adherence. Dizziness and drowsiness are common side effects that diminish with continued use.

Question 16

A patient with a form of epilepsy that may have spontaneous remission has been taking an AED for a year. The patient reports being seizure free for 6 months and asks the nurse when the drug can be discontinued. What will the nurse tell the patient?

Accepted Answer

The most important rule about withdrawing AEDs is that they should be withdrawn slowly over 6 weeks to several months to reduce the risk of status epilepticus (SE). AEDs need not be taken for life if seizures no longer occur. Substituting one AED for another to withdraw AED therapy is not recommended. Stopping an AED abruptly increases the risk of SE.

Quiz 24: Drugs for Epilepsy