W5_04 Anti Seizure Drugs

Question 1

what is anticonvulsant hypersensitivity syndrome (AHS)?

Answer 1

rare, life-threatening ADR in the first 2 months of treatment;
includes fever, rash, liver involvement

Question 2

what kinds of drugs are known to cause AHS?

Answer 2

aromatic amine drugs like

phenobarbital, phenytoin, carbamazepine, lamotrigine

Question 3

which two types of seizures cause diagnostic confusion?

Answer 3

absence and complex partial;

note if absence symptoms present in adulthood, then more likely to be complex partial

Question 4

how likely are patients to respond to the second drug if they don’t respond to the first?

Answer 4

15%; thus, likely intractable

Question 5

what is the most common type of intractable seizure?

Answer 5

complex partial seizure

Question 6

most common co morbidities of seizures?

Answer 6

depression and anxiety

Question 7

fact: patients are more likely to have AED compliance issues than

Answer 7

good

Question 8

how does valproate interact with other drugs?

Answer 8

tends to increase blood levels of other drugs

Question 9

how do phenobarbital, phenytoin, and carbamazepine interact with other drugs?

Answer 9

inducers of P450s, so these tend to cause decreased blood levels of other drugs

Question 10

mechanism for phenytoin and carbamazepine?

Answer 10

hold the voltage-dependent sodium channel in the inactive state

Question 11

mechanism for barbiturates and benzodiazepines?

Answer 11

increase activation of the GABA-A receptor system;

cause sedation of irritability

Question 12

mechanism for ethosuximide?

Answer 12

bind and inhibit t-type voltage dependent calcium channels

Question 13

phenobarbital is used for which types of seizures?

Answer 13

tonic-clonic and partial

Question 14

phenytoin is used for which types of seizures?

Answer 14

tonic-clonic and partial;
note that elimination switches to zero-order if the drug saturates liver enzymes;
can cause ataxic/nystagmic toxicity

Question 15

what is valproate used for?

Answer 15

broad-spectrum seizure drug

Question 16

what is lorazepam used for?

Answer 16

IV benzo for status epilepticus

Question 17

what is carbamazepine used for?

Answer 17

tonic-clonic and partial

Question 18

what is topiramate used for?

Answer 18

broad spectrum;

can cause weight loss, so some people like this drug

Question 19

what is levetiracetam used for?

Answer 19

tonic-clonic and partial;
not many side effects, and neurologists like it a lot;
not well understood

Question 20

what is lamotrigine used for?

Answer 20

broad-spectrum

Question 21

what is clobazam used for?

Answer 21

broad-spectrum;

enhances GABA-A inhibition