W5_04 Anti Seizure Drugs Flashcards
what is anticonvulsant hypersensitivity syndrome (AHS)?
rare, life-threatening ADR in the first 2 months of treatment;
includes fever, rash, liver involvement
what kinds of drugs are known to cause AHS?
aromatic amine drugs like
phenobarbital, phenytoin, carbamazepine, lamotrigine
which two types of seizures cause diagnostic confusion?
absence and complex partial;
note if absence symptoms present in adulthood, then more likely to be complex partial
how likely are patients to respond to the second drug if they don’t respond to the first?
15%; thus, likely intractable
what is the most common type of intractable seizure?
complex partial seizure
most common co morbidities of seizures?
depression and anxiety
fact: patients are more likely to have AED compliance issues than
good
how does valproate interact with other drugs?
tends to increase blood levels of other drugs
how do phenobarbital, phenytoin, and carbamazepine interact with other drugs?
inducers of P450s, so these tend to cause decreased blood levels of other drugs
mechanism for phenytoin and carbamazepine?
hold the voltage-dependent sodium channel in the inactive state
mechanism for barbiturates and benzodiazepines?
increase activation of the GABA-A receptor system;
cause sedation of irritability
mechanism for ethosuximide?
bind and inhibit t-type voltage dependent calcium channels
phenobarbital is used for which types of seizures?
tonic-clonic and partial
phenytoin is used for which types of seizures?
tonic-clonic and partial;
note that elimination switches to zero-order if the drug saturates liver enzymes;
can cause ataxic/nystagmic toxicity
what is valproate used for?
broad-spectrum seizure drug
