Methsuximide

Mechanism-of-action class: Unknown Cellular or Molecular Interaction.

• & USAGE Methsuximide is indicated for the control of absence (petit mal) seizures that are refractory to other drugs.ICD-10: G40.909

• Methsuximide should not be used in patients with a history of hypersensitivity to succinimides.contraindicated

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. Methsuximide may be administered in combination with other anticonvulsants when other forms of epilepsy coexist with absence (petit mal).

Blood dyscrasias Blood dyscrasias, including some with fatal outcome, have been reported to be associated with the use of succinimides; therefore, periodic blood counts should be performed. Should signs and/or symptoms of infection (eg, sore throat, fever) develop, blood counts should be considered at that point. Effects on Liver It has been reported that succinimides have produced morphological and functional changes in animal liver. For this reason, methsuximide should be administered with extreme caution to patients with known liver or renal disease. Periodic urinalysis and liver function studies are advised for all patients receiving the drug. Systemic Lupus Erythematosus Cases of systemic lupus erythematosus have been reported with the use of succinimides. The physician should be alert to this possibility. Suicidal Behavior and Ideation Antiepileptic drugs (AEDs), including methsuximide, increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Patients treated with any AED for any indication should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, and/or any unusual changes in mood or behavior. Pooled analyses of 199 placebo-controlled clinical trials (mono- and adjunctive therapy) of 11 different AEDs showed that patients randomized to one of the AEDs had approximately twice the risk (adjusted Relative Risk 1.8, 95% CI:1.2, 2.7) of suicidal thinking or behavior compared to patients randomized to placebo.

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, blurred vision, photophobia, hiccups, and insomnia. Drowsiness, ataxia, and dizziness have been the most frequent side effects noted. Psychologic abnormalities have included confusion, instability, mental slowness, depression, hypochondriacal behavior, and aggressiveness. There have been rare reports of psychosis, suicidal behavior, and auditory hallucinations. Integumentary System : Dermatologic manifestations which have occurred with the administration of methsuximide have included urticaria, Stevens-Johnson syndrome, and pruritic erythematous rashes. Cardiovascular : Hyperemia. Genitourinary System : Proteinuria, microscopic hematuria. Body as a Whole : Periorbital edema.

PREGNANCY To provide information regarding the effects of in utero exposure to methsuximide, physicians are advised to recommend that pregnant patients taking methsuximide enroll in the (NAAED) Pregnancy Registry. This can be done by calling the toll free number 1-888-233-2334, and must be done by patients themselves. Information on the registry can also be found at the website: http://www.aedpregnancyregistry.org/. See WARNINGS.

Acute overdoses may produce nausea, vomiting, and CNS depression including coma with respiratory depression. Methsuximide poisoning may follow a biphasic course. Following an initial comatose state, patients have awakened and then relapsed into a coma within 24 hours. It is believed that an active metabolite of methsuximide, N-desmethylmethsuximide, is responsible for this biphasic profile. It is important to follow plasma levels of N-desmethylmethsuximide in methsuximide poisonings. Levels greater than 40 μg/mL have caused toxicity, and coma has been seen at levels of 150 μg/mL. Treatment Treatment should include emesis (unless the patient is or could rapidly become obtunded, comatose, or convulsing) or gastric lavage, activated charcoal, cathartics, and general supportive measures. Charcoal hemoperfusion may be useful in removing the N-desmethyl metabolite of methsuximide. Forced diuresis and exchange transfusions are ineffective.

• Feb 8, 1957NDANDA010596Parke Davis
• May 1, 2023ANDAANDA217213Novitium Pharma

1. 1Drug Ineffective2413%
2. 2Seizure2112%
3. 3Convulsion147.8%
4. 4Dizziness137.3%
5. 5Somnolence137.3%
6. 6Feeling Abnormal116.1%
7. 7Generalised Tonic-clonic Seizure116.1%
8. 8Off Label Use116.1%
9. 9Fall95.0%
10. 10Asthenia84.5%
11. 11Drug Interaction84.5%
12. 12Fatigue84.5%
13. 13Therapeutic Product Effect Incomplete73.9%
14. 14Condition Aggravated63.4%
15. 15Toxicity To Various Agents63.4%

The 1 most recently updated of 1 ClinicalTrials.gov registrations naming Methsuximide as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Population Pharmacokinetics of Antiepileptic in Pediatrics
  Completed · Observational · 753 enrolled · Assistance Publique - Hôpitaux de Paris
  NCT03196466updated 2025-11-20

Frequently asked questions

How does Methsuximide work?

Mechanism-of-action class: Unknown Cellular or Molecular Interaction.

What is Methsuximide used for?

According to FDA labeling, Methsuximide carries indications including: & USAGE Methsuximide is indicated for the control of absence (petit mal) seizures that are refractory to other drugs.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Methsuximide?

Methsuximide is classified as Succinimide derivatives, Anti-epileptic Agent, Unknown Cellular or Molecular Interaction, Decreased Central Nervous System Disorganized Electrical Activity, Neurotransmitter & Neuromuscular Transmitter Activity Alteration.

What are the brand names for Methsuximide?

Methsuximide is marketed under brand names including Celontin.

What are the contraindications for Methsuximide?

Methsuximide labeling lists contraindications including: Methsuximide should not be used in patients with a history of hypersensitivity to succinimides.. Always consult the full prescribing information and a clinician.