Brands, Medical Use, Clinical Data
Brands / Synonyms
Aethosuximide; Asamid; Atysmal; Capitus; Emeside; Epileo Petit Mal; Ethosuccimide; Ethosuccinimide; Ethosuxide; Ethymal; Etomal; Etosuximid; Etosuximida; Mesentol; Pemal; Pemalin; Pentinimid; Peptinimid; Petinimid; Petnidan; Piknolepsin; Pyknolepsinum; Ronton; Simatin; Succimal; Succimitin; Suxilep; Suximal; Suxin; Suxinutin; Thetamid; Thilopemal; Uritone; Urodeine; Zaraondan; Zarodan; Zarondan; Zarondan-Saft; Zarontin; Zartalin
For the treatment of petit mal epilepsy.
Used in the treatment of epilepsy. Ethosuximide suppresses the paroxysmal three cycle per second spike and wave activity associated with lapses of consciousness which is common in absence (petit mal) seizures. The frequency of epileptiform attacks is reduced, apparently by depression of the motor cortex and elevation of the threshold of the central nervous system to convulsive stimuli.
Mechanism of Action
Binds to T-type voltage sensitive calcium channels. Voltage-sensitive calcium channels (VSCC) mediate the entry of calcium ions into excitable cells and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, gene expression, cell motility, cell division and cell death. The isoform alpha-1G gives rise to T-type calcium currents. T-type calcium channels belong to the "low-voltage activated (LVA)" group and are strongly blocked by mibefradil. A particularity of this type of channels is an opening at quite negative potentials and a voltage-dependent inactivation. T-type channels serve pacemaking functions in both central neurons and cardiac nodal cells and support calcium signaling in secretory cells and vascular smooth muscle. They may also be involved in the modulation of firing patterns of neurons which is important for information processing as well as in cell growth processes.
Biotrnasformation / Drug Metabolism
Ethosuximide should not be used in patients with a history of hypersensitivity to succinimides.
Since Zarontin (ethosuximide) may interact with concurrently administered antiepileptic drugs, periodic serum
level determinations of these drugs may be necessary (eg, ethosuximide may elevate phenytoin serum levels and
valproic acid has been reported to both increase and decrease ethosuximide levels).