Ethosuximid Chemische Eigenschaften,Einsatz,Produktion Methoden
R-S?tze Betriebsanweisung:
R22:Gesundheitssch?dlich beim Verschlucken.
S-S?tze Betriebsanweisung:
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
Chemische Eigenschaften
White to Off-White Solid
Verwenden
Ethosuximide is an anticonvulsant drug that is used in minor forms of epilepsy.
Definition
ChEBI: A dicarboximide that is pyrrolidine-2,5-dione in which the hydrogens at position 3 are substituted by one methyl and one ethyl group. An antiepileptic, it is used in the treatment of absence seizures and may be used for myoclonic seizures, but is ineffect
ve against tonic-clonic seizures.
Biologische Funktion
It is now generally accepted that the specific antiepileptic
action of ethosuximide (and the older agent trimethadione,
no longer employed) against absence
epilepsy is its ability to reduce the low-threshold calcium
current (LTCC) or T (transient) current. These
currents underlie the 3-Hz spike wave discharges that
are characteristic of absence epilepsy. A blockade of T-calcium current is likely also to be a mechanism used
by valproic acid.
The only clinical use for ethosuximide (Zarontin) is
in the treatment of absence epilepsy. If absence attacks
are the only seizure disorder present, ethosuximide
alone is effective. If other types of epilepsy are present,
ethosuximide can be readily combined with other
agents.
For the most part, ethosuximide is a safe drug. Most
of the side effects are dose related and consist of nausea,
gastrointestinal irritation, drowsiness, and anorexia.
A variety of blood dyscrasias have been reported, but
serious blood disorders are quite rare.
Allgemeine Beschreibung
Ethosuximide is considered the prototypical anticonvulsantneeded for treating patients with absence seizures.Ethosuximide and the N-dealkylated active metabolite ofmethsuximide work by blocking the lowthresholdT-type calcium channels, thereby reducing thehyperexcitability of thalamic neurons that is specifically associatedwith absence seizure.
Clinical Use
Although ethosuximide is the drug of choice for treatment of simple absence seizures, it is not effective against partial complex
or tonic-clonic seizures and may increase the frequency of grand mal attacks. Thus, it must be administered in combination with
other AEDs when treating persons with mixed seizure types. Ethosuximide is a substrate for both CYP3A4 and CYP2E1. The
major metabolite for ethosuximide is 3-(1-hydroxyethyl) succinimide, which is inactive and excreted unconjugated into the urine Several additional metabolites have been characterized recently. Approximately 20% of an oral dose is excreted
unchanged.
Although ethosuximide is thought to be the least toxic of the succinimides, it can cause gastrointestinal disturbances and
dose-related CNS effects, such as drowsiness, dizziness, ataxia, sleep disturbances and depression. Idiosyncratic
hypersensitivity reactions include severe rashes, leukopenia, agranulocytosis (some fatal), systemic lupus erythematosus, and
parkinsonian-like symptoms. In addition to being less toxic than trimethadione, ethosuximide offers a wider range of protection
against different kinds of absence seizures.
Ethosuximid Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte