Unit 5: Chapter 23 (Karch 7th Ed) - Antiseizure Agents

Question 1

1. A patient is admitted to the emergency department with severe recurrent convulsive seizures. What
   drug would the nurse expect to be ordered for use in emergency control of status epilepticus?
   A) Phenytoin (Dilantin)
   B) Diazepam (Valium)
   C) Phenobarbital (Luminal)
   D) Ethosuximide (Zarontin)

Answer 1

Ans: C
Feedback:
Phenobarbital is used for emergency control of status epilepticus. This barbiturate inhibits impulse
conduction in the ascending reticular activating system (RAS), depresses the cerebral cortex, alters
cerebellar function, and depresses motor nerve output. Phenobarbital stabilizes nerve membranes
throughout the central nervous system (CNS) directly by influencing ionic channels in the cell
membrane, thereby decreasing excitability and hyperexcitability to stimulation. By decreasing
conduction through nerve pathways, it reduces the tonic clonic, muscular, and emotional responses to
stimulation. Phenobarbital depresses conduction in the lower brainstem and the cerebral cortex and
depresses motor conduction. Phenytoin is used to prevent status epilepticus but is not used to stop
seizures after they have started; diazepam is used for short-term treatment of status epilepticus.
Ethosuximide is used for absence seizures.

Question 2

2. The pharmacology instructor is discussing drugs used for the treatment of partial seizures. What
   accurately describes the physiological action of carbamazepine?
   A) Reduces electrical activity
   B) Alters sodium and calcium channels
   C) Increases gamma-aminobutyric acid (GABA) activity and blocks sodium and calcium channels to
   stop action potentials
   D) Depresses conduction in the brainstem and cortex

Answer 2

Ans: C
Feedback: Carbamazepine increases GABA activity and blocks sodium and calcium channels to stop action
potentials. Succinimides reduce electrical activity. Acetazolamides reduce electrical activity and alter
sodium and calcium channels. Barbiturates depress conduction in the brainstem and the cortex.

Question 3

3. A 7-year-old girl is brought to the clinic by her mother. The mother states that the child will be engaged
   in some activity at home and then will just stop for a few seconds and then pick up the activity again as
   if there had been no break in what she was doing. The nurse suspects the child might be demonstrating
   what type of seizure?
   A) Tonic clonic seizure
   B) Absence seizure
   C) Myoclonic seizure
   D) Status epilepticus

Answer 3

Ans: B
Feedback:
Absence seizures involve abrupt periods of loss of consciousness lasting 3 to 5 seconds. Tonic-clonic
seizures involve dramatic muscle contractions, loss of consciousness, and a recovery period
characterized by confusion and exhaustion. Myoclonic seizures involve short, sporadic periods of
muscle contractions lasting for several minutes. These types of seizures are rare. Status epilepticus
seizures are the most dangerous and rapidly occur one after another.

Question 4

4. A patient is brought into the emergency department in status epilepticus. The nurse administers
   phenobarbital 320 mg IV according to protocol. Family members ask the nurse how long it will take to
   stop the seizures. What is the nurse’s best response?
   A) The onset of action for the medication is 5 minutes.
   B) We should see results in about 10 minutes.
   C) It will probably take about 30 minutes before the seizures begin to subside.
   D) It may be an hour before the seizures stop.

Answer 4

Ans: A
Feedback:
The onset of IV phenobarbital is 5 minutes; however, it is important not to confuse when the onset of
action will occur and when the seizures will stop because additional interventions may be needed to
stop the seizure activity in some cases. For intramuscular and subcutaneous administration, the onset
should be between 10 and 30 minutes. Onset for an oral dose is between 30 and 60 minutes.

Question 5

5. The nurse evaluates the patient’s serum phenytoin (Dilantin) level and determines the level is
   therapeutic when it is within what range?
   A) Between 5 and 12 mcg/mL
   B) Between 10 and 20 mcg/mL
   C) Between 15 and 50 mcg/mL
   D) Between 40 and 100 mcg/mL

Answer 5

Ans: B
Feedback:
The therapeutic serum level range for phenytoin is between 10 and 20 mcg/mL. The other options are
incorrect.

Question 6

6. A nurse is teaching a patient about his or her newly prescribed drug, phenytoin (Dilantin) for a seizure
   disorder. What will the nurse alert the patient to as a serious adverse effect of this drug?
   A) Drowsiness
   B) Fatigue
   C) Rash
   D) Lethargy

Answer 6

Ans: C
Feedback:
Serious liver, bone marrow, and potentially serious dermatological adverse effects can occur with
phenytoin. Drowsiness, fatigue, and lethargy are adverse effects of hydantoins and classified as not
serious.

Question 7

7. An 8-year-old child has been diagnosed with a seizure disorder and phenytoin (Dilantin) has been
   prescribed for him or her. What nursing diagnosis would be appropriate if the child demonstrated
   adverse effects to the drug?
   A) Deficient fluid volume
   B) Impaired skin integrity related to dermatological effects
   C) Noncompliance for drug therapy
   D) Sleep deprivation

Answer 7

Ans: B
Feedback:
Impaired skin integrity related to dermatological effects would be appropriate because phenytoin can
cause potentially serious dermatological effects as well as gum disease and stained teeth. Usually this
drug will cause the patient to be sleepy all day and should enhance sleep at night. Deficient fluid
volume is not a concern with this drug. Noncompliance will probably not be an issue at this age
because the parents and school nurse will administer the medication.

Question 8

8. A patient is taking ethosuximide (Zarontin) for absence seizures. He or she complains of
   gastrointestinal (GI) upset associated with the drug. The nurse will encourage the patient to do what?
   A) Take the drug 1 hour before or 2 hours after a meal.
   B) Decrease the dosage.
   C) Take the drug with food.
   D) Discontinue the drug and ask his or her physician to prescribe another drug.

Answer 8

Ans: C
Feedback:
If GI irritation occurs with ethosuximide, the patient should be encouraged to take the medication with
food to reduce this adverse effect. A nurse would never tell a patient to decrease the dosage or
discontinue a drug. That advice should only be given by the patient’s medication prescriber. Taking the
drug 1 to 2 hours after meals would not reduce this effect.

Question 9

9. The drug of choice for the treatment of partial seizures is what?
A) Carbamazepine (Tegretol)
B) Clorazepate (Tranxene)
C) Felbamate (Felbatol)
D) Gabapentin (Neurontin)

Answer 9

Ans: A
Feedback:
Carbamazepine is often the drug of choice for treatment of partial seizures. It has the ability to inhibit
polysynaptic responses and to block sodium channels to prevent the formation of repetitive action
potentials in the abnormal focus. Clorazepate is indicated for anxiety and alcohol withdrawal and used
as adjunctive therapy for partial seizures. Felbamate has been associated with severe liver failure and
aplastic anemia and is now reserved for those patients who do not respond to other therapies.
Gabapentin is used as adjunctive therapy in the treatment of partial seizures and for the treatment of
postherpetic neuralgia.

Question 10

10. A patient who has been taking lamotrigine (Lamictal) for the past 2 weeks calls the clinic and reports to
    the nurse that he or she has developed a rash. What should the nurse tell him or her to do?
    A) To continue taking the drug and that the rash will go away
    B) To talk to he or she physician and that he will prescribe a cream to apply to the rash
    C) To decrease the dosage by half for 2 weeks and then take the prescribed dose
    D) To discontinue the drug and return to the clinic immediately

Answer 10

Ans: D
Feedback:
The nurse should inform the patient to discontinue the drug and return to the clinic. Rashes associated
with the use of lamotrigine can be life-threatening. The patient needs to return to the clinic to be
evaluated and will need a change of medication. Discontinuing the medication will cause the rash to
clear. The nurse is not licensed to adjust the dosage of a drug for a patient.

Question 11

11. The school nurse sees a child on the playground have an absence seizure identified by the occurrence of
    what characteristics?
    A) Alterations in consciousness that last seconds
    B) Automatic and repetitive movements
    C) Abnormal movements and bizarre behavior
    D) Sustained contraction of skeletal muscle

Answer 11

Ans: A
Feedback:
Absence seizures are characterized by abrupt alterations in consciousness that last only a few seconds.
Characteristics of an absence seizure do not include automatic and repetitive movements, abnormal
movements and bizarre behavior, or sustained contraction of skeletal muscle.

Question 12

12. The nurse is providing patient education for a patient newly prescribed a hydantoin antiseizure
    medication. What would the nurse be sure to teach the patient regarding the dangers of abrupt
    withdrawal?
    A) Hypertensive crisis
    B) Cardiac dysrhythmias
    C) Respiratory arrest
    D) Status epilepticus

Answer 12

Ans: D
Feedback:
Discontinuing hydantoins could result in status epilepticus so that drugs should be withdrawn, or added
to the medication regimen, carefully to avoid danger. An abrupt withdrawal of antiseizure medications
would not precipitate hypertensive crisis, dysrhythmias, or respiratory arrest.

Question 13

13. A patient is brought to the emergency department in the midst of an active clonic tonic seizure. What is
    the most appropriate antiseizure drug for the nurse to administer intravenously to terminate acute
    convulsive seizures?
    A) Diazepam (Valium)
    B) Phenytoin (Dilantin)
    C) Ethosuximide (Zarontin)
    D) Gabapentin (Neurontin)

Answer 13

Ans: A
Feedback:
The drug of choice for acute seizures is intravenous benzodiazepine, usually diazepam. Phenytoin is
administered to control and prevent seizures but is not the drug of choice to stop an active seizure.
Gabapentin and ethosuximide are administered for partial seizures.

Question 14

14. The nurse is caring for a patient receiving ethotoin to control seizure activity. When reviewing the
    patient’s laboratory results, the nurse would assess the patient is in a therapeutic level when the lab
    result is within what range?
    A) 5 to 15 mcg/mL
    B) 10 to 20 mcg/mL
    C) 15 to 50 mcg/mL
    D) 20 to 30 mcg/mL

Answer 14

Ans: C
Feedback:
Therapeutic serum ethotoin levels range between 15 and 50 mcg/mL. Options A, B, and D are
incorrect

Question 15

15. The nurse, working in the emergency room, admits a 13-month-old child reported by the parents to
    have had a clonic tonic seizure at home with no history of a seizure disorder. What is the nurse’s priority
    intervention?
    A) Monitor serum phenytoin level.
    B) Take the child’s temperature.
    C) Place the child in a tepid bath.
    D) Administer an antipyretic medication.

Answer 15

Ans: B
Feedback:
The first action of the nurse is to measure body temperature to determine whether the child has a fever,
which could explain why the seizure occurred. Febrile seizures are common in young children. They
are related to very high fevers and usually involve clonic tonic seizure. Febrile seizures most frequently
occur in children and they are usually self-limited and do not reappear. The nurse would not treat a
fever by administering antipyretics or providing a tepid bath until temperature is measured. There
would be no reason to check phenytoin levels if the child has no history of seizure disorder.

Question 16

16. Richard, 15 years old, has been diagnosed with epilepsy. He is to be sent home on oral phenytoin 100
    mg b.i.d. What statement by Richard’s mother leads the nurse to believe she has understood drug
    teaching?
    A) I will make sure he takes the medication on an empty stomach.
    B) I will stop the drug immediately if any side effects occur.
    C) I will make sure he has routine visits to the dentist.
    D) I will weigh him daily and feed him a high-calorie diet.

Answer 16

Ans: C
Feedback:
Gingival hyperplasia is common in patients, especially children, who take phenytoin, which makes
regular dentist visits important to oral health. Taking the medication on a full stomach or with meals
reduces gastrointestinal (GI) adverse effects. The mother should call the health care provider if adverse
effects are noted and needs to understand the risks associated with abrupt withdrawal of the medication.
Daily weight taking and high-calorie diets are not associated with phenytoin administration.

Question 17

17. The mother of a child newly diagnosed with drug-resistant epilepsy asks the nurse why two
    antiepileptic drugs have been prescribed for her daughter. What is the nurse’s best answer?
    A) To decrease overall cost
    B) To decrease risk of adverse effects
    C) To minimize seizures in resistant epilepsy
    D) To increase movement of sodium ions into the cell

Answer 17

Ans: C
Feedback:
When monotherapy is ineffective, a second, and sometimes a third, drug may be added in an attempt to
control seizures. It does not decrease overall cost or reduce the risk of side effects or increase
movement of sodium ions into the cell

Question 18

18. The patient’s serum drug level is elevated and indicates a toxic level. What will the nurse assess for in
this patient? (Select all that apply.)
A) Liver toxicity
B) Bone marrow suppression
C) Serious dermatological reactions
D) Tooth loss
E) Renal damage

Answer 18

Ans: A, B, C
Feedback:
Toxic levels of phenytoin increase the likelihood of adverse effects so the nurse would assess for liver
toxicity, bone marrow suppression, or serious dermatological reactions. Gingival hyperplasia, not tooth
loss, is associated with phenytoin toxic effects. Renal damage is not associated with phenytoin.

Question 19

19. A patient has a new order for carbamazepine (Tegretol). What does the nurse know is a
    contraindication to administration of carbamazepine?
    A) Bone marrow depression
    B) Bipolar disorder
    C) Allergy to sulfonamides
    D) Diabetes

Answer 19

Ans: A
Feedback:
Bone marrow suppression would be considered a contraindication to administration of carbamazepine
therapy. Contraindications to the use of Tegretol do not include bipolar disorder, an allergy to
sulfonamides, or diabetes.

Question 20

20. A patient with liver impairment needs an antiepileptic drug. What drug would be safest for patients
with liver impairment?
A) Levetiracetam (Keppra)
B) Lamotrigine (Lamictal)
C) Phenobarbital
D) Valproic acid (Depakene)

Answer 20

Ans: A
Feedback:
Levetiracetam is a newer drug chemically unrelated to other antiepileptic drug. Most of the drug is
excreted by the kidneys and is not metabolized by the liver so it would be safer for the patient with liver
disease. The other options are all metabolized by the liver, so the patient with liver disease will need a
lower dosage.

Question 21

21. The nurse is caring for a patient diagnosed with generalized seizures and will appropriately administer
    what classifications of medications to this patient? (Select all that apply.)
    A) Succinimides
    B) Acetazolamide
    C) Valproic acid
    D) Hydantoin
    E) Benzodiazepines

Answer 21

Ans: D, E
Feedback:
Drugs used to treat generalized seizures include the hydantoins, barbiturates, and benzodiazepines.
Drugs used to treat absence seizures a particular type of generalized seizure include the hydantoins,
succinimides, acetazolamide, valproic acid, and zonisamide.

Question 22

22. The nurse is caring for a 4-year-old child diagnosed with a seizure disorder requiring an antiseizure
    agent. Using mg/kg as the comparison, how will the child’s dose compare with an adult s dose?
    A) Children require a smaller mg/kg dose than an adult.
    B) Children require a larger mg/kg dose than an adult.
    C) Mg/kg dose is the same for adults and children.
    D) Dosing varies by medication.

Answer 22

Ans: B
Feedback:
Older children (2 months to 6 years of age) absorb and metabolize many of these drugs more quickly
than adults and require a larger dosage per kilogram to maintain therapeutic levels.

Question 23

23. What factors contribute to determining the drug of choice for a patient with epilepsy? (Select all that
    apply.)
    A) Age
    B) Type of epilepsy
    C) Patient characteristics
    D) Preferred adverse effect
    E) Gender

Answer 23

Ans: A, B, C
Feedback:
The drug of choice for any given situation depends on the type of epilepsy, patient age, specific patient
characteristics such as cultural variations, and patient tolerance for associated adverse effects as
opposed to preferred adverse effect. No adverse effects would be preferred but, because nearly all drugs
have some adverse effects, determining what is tolerable to a particular patient is important to consider.
Gender does not play a role in determining drug of choice.

Question 24

24. The nurse anticipates a reduced dosage due to cultural differences when caring for patients from what
    cultural groups? (Select all that apply.)
    A) Arab Americans
    B) Asian Americans
    C) African Americans
    D) White American
    E) Native American

Answer 24

Ans: A, B
Feedback:
Because of differences in liver enzyme functioning among Arab Americans and Asian Americans,
patients in these ethnic groups may not metabolize antiseizure agents in the same way as patients in
other ethnic groups. They may require not only lower doses to achieve the same therapeutic effects but
also frequent dose adjustment. Nothing indicates a need to alter dosage for African Americans, Whites,
or Native Americans

Question 25

25. A patient with a seizure disorder has had a recent change in medication. What data would the nurse
    collect to evaluate the effectiveness of the new drug? (Select all that apply.)
    A) Evaluate vital signs.
    B) Evaluate laboratory drug level.
    C) Assess for adverse effects.
    D) Assess for change in seizure activity.
    E) Assess for cost of therapy.

Answer 25

Ans: B, C, D
Feedback:
Interview and assess for any change in seizure activity; interview and assess for avoidance of adverse
drug effects, especially those that impair safety; when available, check laboratory reports of serum drug
levels for therapeutic ranges or evidence of underdosing or overdosing. Measuring vital signs is part of
every patient visit but does not contribute to evaluation of drug effectiveness. For example, if the
patient has had a sudden increase in number of seizures, but is not currently having a seizure, vital signs
will likely be within normal range. Cost of therapy does not indicate the effectiveness of drugs. Cost
should be considered when prescribing drugs, not when they are being evaluated.

Question 26

26. A patient is brought in to the emergency department by ambulance in status epilepticus. What drug may
be used for this patient?
A) Carbamazepine
B) Clorazepate
C) Ethotoin
D) Fosphenytoin

Answer 26

Ans: D
Feedback:
Only fosphenytoin is indicated for the treatment of status epilepticus. Carbamazepine is used to treat
seizure disorders as well as trigeminal neuralgia and bipolar disorder but it is not indicated for status
epilepticus. Clorazepate and ethotoin are used in long-term treatment of partial seizure disorders, alone,
or with other antiepileptic drugs but would not be used for status epilepticus.

Question 27

27. The patient has serum drug levels of an antiepileptic drug ordered. The patient asks the nurse why drug
    levels are measured. What is the nurse’s best response?
    A) To evaluate whetherthe therapeutic range is reached
    B) To measure the amount of toxicity
    C) To determine the effect of the drug on body systems
    D) To evaluate the effectiveness of therapy

Answer 27

Ans: A
Feedback:
Measuring serum drug levels evaluates whether the therapeutic range of circulating drug can be found
in the serum. It does not measure toxicity, which can occur even when the drug level is within
prescribed range, and it does not evaluate effectiveness of therapy, which can only be evaluated by
determining whether the drug is having the desired effect of reducing number of seizures. To determine
the effect the drug is having on other body systems, it would be necessary to draw lab levels that
measure functioning of that particular system.

Question 28

28. The nursing instructor is discussing absence seizures and how to treat them in children. A student asks
    the difference between ethosuximide and methsuximide, the drugs used to control absence seizures.
    What is the instructor s best response?
    A) Ethosuximide has more severe adverse effects than methsuximide.
    B) Seizures are more refractory to methsuximide.
    C) There is no real difference in the drugs.
    D) Methsuximide has more severe adverse effects than ethosuximide.

Answer 28

Ans: D
Feedback:
Ethosuximide and methsuximide are indicated for the control of absence seizures. Ethosuximide should
be tried first; methsuximide should be reserved for the treatment of seizures that are refractory to other
agents because it is associated with more severe adverse effects.

Question 29

29. A patient, newly diagnosed with a seizure disorder, has been prescribed valproic acid. What is one
    adverse effect of valproic acid that the nurse should include in the medication teaching plan?
    A) Liver toxicity
    B) Esophageal irritation
    C) Cardiac insufficiency
    D) Muscle weakness

Answer 29

Ans: A
Feedback:
Valproic acid is associated with liver toxicity. Esophageal irritation, cardiac insufficiency, and muscle
weakness are not associated with valproic acid therapy.

Question 30

30. While writing a care plan for a patient newly diagnosed with generalized seizures, the nurse might
    appropriately choose what nursing diagnosis?
    A) Risk for injury related to gastrointestinal (GI) effects
    B) Disturbed thought processes related to central nervous system effects
    C) Monitor complete blood count (CBC) before and periodically during therapy.
    D) Offer support and encouragement.

Answer 30

Ans: B
Feedback:
Disturbed thought processes related to central nervous system (CNS) effects is a nursing diagnosis for a
patient receiving any antiepileptic medication for generalized seizures. Monitoring CBC and offering
support and encouragement are implementations rather than diagnosis. Risk for injury is incorrect
because the risk for injury to this patient is from the CNS effects and not GI effects.

Question 31

31. The patient, newly diagnosed with epilepsy, asks the nurse to explain the meaning of the diagnosis.
    What is the nurse’s best response?
    A) Epilepsy is a single disease that causes seizures.
    B) Epilepsy is a convulsive disorder caused by electrical discharge in the muscle.
    C) Epilepsy is characterized by sudden discharge of excessive electrical energy.
    D) Epilepsy is the tonic clonic muscle contractions with potential to cause injury.

Answer 31

Ans: B
Feedback:
The most prevalent of the neurological disorders, epilepsy is not a single disease but a collection of
different syndromes characterized by the same feature: sudden discharge of excessive electrical energy
from nerve cells located within the brain, which leads to a seizure. In some cases, this release stimulates
motor nerves, resulting in convulsions, with tonic clonic muscle contractions that have the potential to
cause injury, tics, and spasms. Other discharges may stimulate autonomic or sensory nerves and cause
very different effects, such as a barely perceptible, temporary lapse in consciousness or a sympathetic
reaction.

Question 32

32. The nurse is providing patient teaching with a patient who is newly diagnosed with epilepsy. The
    patient asks, Can I still drive to work? What is the nurse’s best response?
    A) Not until your seizures are controlled by medication
    B) Yes, as long as you take your medications regularly.
    C) You can drive as soon as therapeutic drug levels are obtained.
    D) Epileptics need to use public transportation because a seizure could occur anytime.

Answer 32

Ans: A
Feedback:
Patients newly diagnosed with epilepsy will not be able to drive. However, after the patient’s seizures
are controlled (usually for 6 months to 2 years depending on state law), the patient may be able to
regain the ability to drive.

Question 33

33. The nurse is caring for an 84-year-old patient in the acute care facility who was newly diagnosed with a
    seizure disorder. Before starting the patient on an antiepileptic medication that will be continued after
    discharge, what laboratory studies would the nurse want to assess? (Select all that apply.)
    A) Serum drug levels
    B) Liver function studies
    C) Renal function studies
    D) Cardiovascular function studies
    E) Central nervous system function studies

Answer 33

Ans: B, C
Feedback:
Baseline kidney and liver function tests should be done and results will guide dosing of the antiepileptic
medication because patients with liver or kidney disease will require lower dosages of medication.
Serum drug levels will not be drawn until after specific medications are started. Cardiovascular and
central nervous system function studies are not indicated.

Question 34

34. The patient has a seizure that causes rhythmic twitching of the left hand for 90 seconds with no loss of
    consciousness and then stops. The nurse notes this same action repeated many times throughout the day
    and documents this as what type of seizure?
    A) Myoclonic seizure
    B) Jacksonian seizure
    C) Psychomotor seizure
    D) Simple partial seizure

Answer 34

Ans: D
Feedback:
This patient is having simple partial seizures, which occur in a single area of the brain and may involve
a single muscle movement or sensory alteration. Myoclonic seizures involve short, sporadic periods of
muscle contractions that last for several minutes. Jacksonian seizures begin in one area of the brain and
involve one part of the body and then progressively spread to other parts of the body; they can develop
into generalized tonic clonic seizures. Psychomotor seizures are complex seizures that involve sensory,
motor, and psychic components.

Question 35

35. What antiepileptic classification of drugs works by stabilizing nerve membranes by influencing ionic
    channels in the cell membrane, thereby decreasing excitability and hyperexcitability to stimulation?
    A) Hydantoins
    B) Benzodiazepines
    C) Valproic acid
    D) Carbamazepine

Answer 35

Ans: A
Feedback: The hydantoins stabilize nerve membranes throughout the central nervous system directly by
influencing ionic channels in the cell membrane, thereby decreasing excitability and hyperexcitability
to stimulation. By decreasing conduction through nerve pathways, they reduce the tonic clonic,
muscular, and emotional responses to stimulation. Valproic acid and benzodiazepines increase gammaaminobutyric
acid (GABA) effects and decrease electrical activity. Carbamazepine increases GABA
activity and blocks sodium and calcium channels to stop action potentials.