Here are a couple of questions related to the pharmacology of anticonvulsants. These questions from the UMKC School of Medicine have a different degree of difficulty, but are useful to review the topic.
Note: the FDA has recently issued an alert on an increased risk of suicide and antiepileptics.
Item Number: 8227 correct answer: 5 category: Anticonvulsants
1. Drugs most often used in the treatment of petit mal epilepsy include:
1. ethosuximide
2. phenytoin
3. sodium valproate
4. All of the above
5. 1,3Item Number: 2095 correct answer: 4 category: Anticonvulsants
2. The most specific agent for treatment of petit mal epilepsy is:
1. carbamazepine
2. phenytoin
3. gabapentin
4. ethosuximide
5. primidoneItem Number: 9733 correct answer: 5 category: Anticonvulsants
3. Phenytoin may have adverse effects on the hematopoietic system. All of the
following have been reported EXCEPT:
1. macrocytic anemia
2. hepatosplenomegaly
3. folic acid deficiency
4. lymphadenopathy
5. leukemia
Item Number: 6929 correct answer: 5 category: Anticonvulsants
4. The drug of choice in initiating chronic treatment of grand mal epilepsy is:
1. phenobarbital
2. ethosuximide
3. phenacemide
4. diazepam
5. carbamazepineItem Number: 4399 correct answer: 2 category: Anticonvulsants
5. Gingival hyperplasia is a common side effect of:
1. procainamide
2. phenytoin
3. digitalis
4. indomethacin
5. guanethidineItem Number: 9738 correct answer: 1 category: Anticonvulsants
6. Carbamazepine is considered to be a primary drug for treatment of all types of
epilepsy except absence seizures. Its indications and proposed mechanism of
action are most closely related to:
1. phenytoin
2. phenobarbital
3. ethosuximide
4. primidone
5. diazepamItem Number: 6762 correct answer: 3 category: Anticonvulsants
7. Anticonvulsants which have active metabolites include:
A. phenytoin
B. primidone
C. phenobarbital
D. carbamazepine
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 7646 correct answer: 1 category: Anticonvulsants
8. Carbamazepine toxicities include:
A. water retention
B. dystonia and myoclonus
C. diplopia, blurred vision, and vertigo
D. gingival Hyperplasia
1. A,B,C
2. A,C
3. B,D
4. D only
5. All are correctItem Number: 6099 correct answer: 4 category: Anticonvulsants
9. Prolonged dilantin use may lead to:
1. vitamin A deficiency
2. hypoglycemia
3. folic acid, iron, and vitamin C deficiency
4. abnormality in folic acid metabolism
5. thiamine deficiencyItem Number: 6903 correct answer: 1 category: Anticonvulsants
10. Visual disturbances (such as “halos” on objects) are a side effect of
which of the following anticonvulsants?
1. trimethadione
2. phenytoin
3. phenacemide
4. phenobarbital
5. ethosuximideItem Number: 6763 correct answer: 5 category: Anticonvulsants
11. Pharmacokinetic blood level monitoring is apt to be most helpful for
which of the following anticonvulsants?
A. phenytoin
B. primidone
C. phenobarbital
D. carbamazepine
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6386 correct answer: 3 category: Anticonvulsants
12. A patient with pulmonary disease is taking prednisone. You begin her on
phenytoin therapy for a newly diagnosed seizure disorder. Two weeks later the
patient returns to the clinic to see you and complains that her pulmonary
disease has worsened since she began the phenytoin therapy. A likely reason
for this new change is that phenytoin:
1. interferes with absorption of the prednisone
2. stabilizes cell membranes, preventing the prednisone from diffusing to
the site of action
3. accelerates hepatic degradation of the prednisone
4. induce renal excretory pathways, accelerating urinary excretion of the
prednisone
5. activates the asthma directlyItem Number: 6909 correct answer: 3 category: Anticonvulsants
13. Drugs which are effective in the management of petit mal seizures include:
A. phenytoin
B. clonazepam
C. primidone
D. valproate
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6768 correct answer: 1 category: Anticonvulsants
14. Treatment of complex partial (temporal lobe) seizures generally requires the
use of:
A. phenytoin
B. phenobarbital
C. carbamazepine
D. ethosuximide
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6408 correct answer: 3 category: Anticonvulsants
15. Antiarthritic drugs not presently known to interact with phenytoin therapy
include:
A. salicylates
B. cyclophosphamide
C. phenylbutazone
D. gold
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 7425 correct answer: 4 category: Anticonvulsants
16. A 21-year-old male has been brought to the emergency room unconscious three
hours after ingestion of a large dose of barbiturate. The immediate method of
management would be:
1. administer concentrated dextrose intravenously
2. perform hemodialysis immediately with an artificial kidney
3. administer an analeptic drug such as pentylenetetrazol
4. maintain a clear airway and artificially assist ventilation if air
exchange is unsatisfactory
5. perform gastric lavage immediately with warm tap waterItem Number: 10777 correct answer: 1 category: Anticonvulsants
17. The liver function test most frequently elevated in patients taking
phenytoin is:
1. gamma-glutamyl transpeptidase (GGTP)
2. serum glutamic oxaloacetic transaminase (SGOT)
3. serum glutamic pyruvic transaminase (SGPT)
4. lactic acid dehydrogenase (LDH)
5. alkaline phosphataseItem Number: 6777 correct answer: 3 category: Anticonvulsants
18. Which of the following drugs (including metabolites) would achieve steady
state blood level concentrations earliest assuming a loading dose is not
given?
1. phenytoin
2. primidone
3. valproate
4. phenobarbital
5. ethosuximideItem Number: 6936 correct answer: 4 category: Anticonvulsants
19. The administration of one drug may stimulate the metabolism of another drug
(enzyme induction). Phenobarbital is an example of such an enzyme inducer.
The metabolism of which of the following drugs may be affected by
phenobarbital administration?
1. warfarin
2. phenytoin
3. digitoxin
4. All of the above
5. 1,2Item Number: 6418 correct answer: 4 category: Anticonvulsants
20. A patient you are following in the hospital is not responding to appropriate
doses of phenytoin therapy (blood level 1.8 mg/dl). The decision is made to
begin phenobarbital therapy immediately. The docent requests that you suggest
a loading regimen for this 70-kg male patient to achieve a blood level of 2.0
mg/dl within 24 hours (volume of distribution of phenobarbital = 0.75 l/kg).
Your suggestion would be:
1. 15 mg
2. 150 mg
3. 1.5 mg/kg
4. 1000 mg
5. It is not possible to calculate regimen without additional dataItem Number: 7963 correct answer: 4 category: Anticonvulsants
21. In the differential diagnosis of hirsutism, drug-induced hirsutism must be
considered. A drug which is known to include hirsutism as a side- effect is:
1. thallium
2. heparin
3. cephalosporins
4. phenytoin
5. diazepamItem Number: 10780 correct answer: 5 category: Anticonvulsants
22. Drugs known to be effective for generalized tonic-clonic seizures include:
A. phenytoin
B. primidone
C. carbamazepine
D. valproic acid
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6781 correct answer: 3 category: Anticonvulsants
23. Drugs which have been shown to be effective for the chronic management
of absence seizures include:
A. phenytoin
B. valproate
C. primidone
D. ethosuximide
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6423 correct answer: 3 category: Anticonvulsants
24. A Patient you began on carbamazepine recently has returned to your office
complaining of headache, vomiting, and dizziness. The patient is mildly
confused. Laboratory data were: sodium 112 mEq/L, potassium 3.9 mEq/L,
chloride 90 mEq/L, BUN 12 mg/dl and albumin 3.2 G/dl (normal values for lab:
sodium 135-148, potassium 3.0-5.3, chloride 96-107, BUN 7-22, albumin
3.8-4.8). Which of the following best explains this patient’s symptomatology?
A. carbamazepine-Induced megaloblastic anemia
B. carbamazepine-Induced hyponatremia
C. carbamazepine-Induced cerebellar degeneration
D. carbamazepine-Induced central nervous system toxicity (blood level
related)
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6880 correct answer: 5 category: Anticonvulsants
25. Grand mal epilepsy can be effectively treated in some patients with:
A. phenytoin
B. carbamazepine
C. phenobarbital
D. valproate
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 10786 correct answer: 4 category: Anticonvulsants
26. Drugs known to increase the concentration of phenytoin when given
concomitantly include:
A. carbamazepine
B. enteral feedings
C. quinidine gluconate
D. disulfiram
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6790 correct answer: 3 category: Anticonvulsants
27. Which of the following anticonvulsants is (are) administered as a single daily
dose?
A. valproic acid
B. phenobarbital
C. carbamazepine
D. phenytoin
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6447 correct answer: 2 category: Anticonvulsants
28. A 26-Year-old female suffering from complex partial seizures is receiving
treatment with phenytoin 400 mg (blood level 11 mg/L), and carbamazepine 600
mg/day (blood level 5.3 mg/L). She currently reports having two or three
seizures every three to four months. Despite treatment with lo/Ovral
(norgestrel 0.3 mg with ethinyl estradiol 30 mcg), she has learned that she is
pregnant. Possible reasons for this complication include:
A. poor compliance with the lo/Ovral
B. increased pituitary gonadotropin secretion secondary to phenytoin
C. anticonvulsant induced microsomal enzyme induction, causing more
rapid metabolism of the lo/Ovral
D. increased pituitary gonadotropin secretion secondary to
carbamazepine
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6890 correct answer: 1 category: Anticonvulsants
29. Phenytoin is hydroxylated by liver microsomes. The amount of drug oxidized
is:
A. increased by chronic administration of carbamazepine
B. decreased by simultaneous administration of isoniazid
C. decreased by concurrent administration of disulfiram
D. increased by simultaneous administration of chloramphenicol
1. A,B,C
2. A,C
3. B,D
4. D only
5. None of the aboveItem Number: 10787 correct answer: 3 category: Anticonvulsants
30. Your patient is a 35-year-old epileptic who takes phenytoin 300 mg daily and
primidone 500 mg every eight hours daily. He visits you in clinic complaining
of a recent (Past 1-2 days) increase in seizure frequency. He claims to be
very compliant with his medicine and states that he took his last dose 1.5
hours prior to his clinic visit. Following chart review you request stat drug
levels. These are reported back to you as phenobarbital=12 mcg/mL (15-40),
primidone=0 (5-12), and phenytoin=5 mcg/mL (10-20). Statements which could
explain the drug levels observed include:
A. an unusually high degree of hepatic microsomal enzyme induction
B. compliance is questionable…you strongly suspect that he has
taken no medicine for the past two days
C. the patient did take both of his seizure medicines 1.5 hours
before his clinic visit; however, he probably did not take any for
3-4 days before that time
D. the patient may have been compliant with phenytoin recently (past
1-2 days), but not with his primidone
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6799 correct answer: 3 category: Anticonvulsants
31. Variability in absorption represents one potential source for variation in
steady state blood levels. Anticonvulsants associated with variable
absorption include:
A. primidone
B. phenytoin
C. ethosuximide
D. carbamazepine
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 10704 correct answer: 1 category: Anticonvulsants
32. The most appropriate drug for treatment of generalized tonic-clonic (grand
mal) is:
1. valproate
2. methylphenidate
3. ethosuximide
4. diazepam
5. trimethadioneItem Number: 6796 correct answer: 1 category: Anticonvulsants
33. Since it’s introduction in 1938, Phenytoin has been a major anticonvulsant
drug in the treatment of epilepsy. Phenytoin therapy has been shown to be of
value for which of the following seizure types?
A. complex partial seizures (psychomotor)
B. generalized tonic clonic
C. elementary partial (focal)
D. absences
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 6888 correct answer: 5 category: Anticonvulsants
34. Drugs useful in the management of temporal-lobe epilepsy include:
1. trimethadione
2. carbamazepine
3. phenytoin
4. diazepam
5. 2,3Item Number: 12915 correct answer: 1 category: Anticonvulsants
35. A patient comes to the office complaining of sore, enlarged gums. She is
currently taking medication for hypertension and phenobarbital and phenytoin
for seizures. The fibrous hyperplasia is most probably due to:
1. phenytoin
2. excessive brushing of teeth
3. propranolol
4. staphylococci infection of gums
5. phenobarbitalItem Number: 6451 correct answer: 2 category: Anticonvulsants
36. Which of the following anticonvulsants can be administered as a drug and is
also a metabolite of one of the other agents?
1. phenytoin
2. phenobarbital
3. primidone
4. carbamazepine
5. ethosuximideItem Number: 7665 correct answer: 5 category: Anticonvulsants
37. Correct statements concerning valproic acid toxicity include:
A. VPA has been associated with thinning of the hair
B. VPA has been associated with benign essential tremor
C. VPA has been associated with thrombocytopenia
D. VPA has been associated with hepatitis, which usually occurs
within the initial six months of therapy
1. A,B,C
2. A,C
3. B,D
4. D only
5. All are correctItem Number: 9595 correct answer: 4 category: Anticonvulsants
38. The generic anticonvulsant diphenylhydantoin is now officially called
phenytoin. Common adverse effects of chronic phenytoin therapy include all of
the following EXCEPT:
1. gingival hyperplasia
2. morbilliform skin rash
3. hirsutism
4. hypoglycemia
5. ataxiaItem Number: 12984 correct answer: 4 category: Anticonvulsants
39. Phenytoin toxicity can cause:
1. behavioral changes
2. increased frequency of seizures
3. gingival hyperplasia
4. All of the above
5. 1,3Item Number: 6471 correct answer: 1 category: Anticonvulsants
40. Correct statements concerning the use of diazepam for the emergency management
of status epilepticus include:
A. diazepam should be given intravenously to ensure a rapid onset of
action
B. diazepam should be given slowly to minimize the potential
cardiovascular and respiratory complications (Max OF 5 mg/min)
C. diazepam should not be expected to provide long-term control in
status epilepticus because serum levels of the drug fall secondary
to its extensive distribution in the body
D. diazepam should be used only for status epilepticus of the tonic-
clonic (grand mal) type
1. A,B,C
2. A,C
3. B,D
4. D only
5. All of the aboveItem Number: 1602 correct answer: 5 category: Anticonvulsants
41. You prescribe phenytoin for a young girl with epilepsy. Her mother calls one
month later to inquire about possible side effects. All of the following may
be side effects EXCEPT:
1. nystagmus
2. ophthalmoplegia
3. gingival hyperplasia
4. ataxia
5. None of the above; all are possible side effects