Overview
DESCRIPTION Methsuximide is an anticonvulsant succinimide, chemically designated as N,2-Dimethyl-2-phenylsuccinimide, with the following structural formula: Each Methsuximide Capsule, USP contains 300 mg methsuximide, USP. Also contains corn starch, colloidal silicon dioxide and magnesium stearate. The capsule shells contain gelatin, purified water, sodium lauryl sulfate, D&C Yellow No.
Mechanism of Action
CLINICAL PHARMACOLOGY Methsuximide 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.
Indications
- INDICATIONS & USAGE Methsuximide is indicated for the control of absence (petit mal) seizures that are refractory to other drugs.
Common Doses
- 300 mg
- 1.2 g
Dosage
DOSAGE & ADMINISTRATION Optimum dosage of methsuximide must be determined by trial. A suggested dosage schedule is 300 mg per day for the first week. If required, dosage may be increased thereafter at weekly intervals by 300 mg per day for the three weeks following to a daily dosage of 1.2 g. Because therapeutic effect and tolerance vary among patients, therapy with methsuximide must be individualized according to the response of each patient. Optimal dosage is that amount of methsuximide which is barely sufficient to control seizures so that side effects may be kept to a minimum.
Contraindications
- CONTRAINDICATIONS Methsuximide should not be used in patients with a history of hypersensitivity to succinimides.
Side Effects
- ADVERSE REACTIONS Gastrointestinal System: Gastrointestinal symptoms occur frequently and have included nausea or vomiting, anorexia, diarrhea, weight loss, epigastric and abdominal pain, and constipation. Hemopoietic System: Hemopoietic complications associated with the administration of methsuximide have included eosinophilia, leukopenia, monocytosis, and pancytopenia with or without bone marrow suppression. Nervous System : Neurologic and sensory reactions reported during therapy with methsuximide have included drowsiness, ataxia or dizziness, irritability and nervousness, headache,...
Interactions
- DRUG INTERACTIONS Since methsuximide may interact with concurrently administered antiepileptic drugs, periodic serum level determinations of these drugs may be necessary (eg, methsuximide may increase the plasma concentrations of phenytoin and phenobarbital).