Antiseizure Drugs

As the different types of seizure are diverse, so too are the different treatments that are used.

Treatment specificity is especially true with the absence type seizure.

Animal models have been useful for identiying drugs useful for treating epilepsy.

maximal elecroshock tests mimicks generalized tonic0clonic seizures and complex partial seizures

limbic seizures brought on by electrical kindling mimicks complex partial seizures

All anticonvulsant drugs have idiosyncratic or dose-dependent side effects. Treatment doses are increased until either seizure control occurs or dose-limiting side effects appear.

Benzodiazepines can be used to end seizures.

 

Mechanisms of anti-seizure drugs

Enhancement of GABA action

works against a variety of seizures

Inhibition of sodium channel function

good for partial seizures

Inhibition of Calcium T-type channels

Used as adjuncts

Structure

most older anti-seizure drugs were based on a heterocyclic ring; newer ones are not

 

Pharmacokinetics

Most antiseizure drugs have oral activity, are well absorbed, and enter the CNS. Most are not highly bound to plasma proteins.

Antiseizure drugs are cleared chiefly by hepatic metabolism and clearance in stool.

Half-lives of antiseizure dtugs tend to be long - some over 12 hours.