Product Name


CAS Number


LGM Pharma is an API distributor. LGM Pharma supplies APIs as per CGMP with DMF support, subject to availability and manufacturer requirements. LGM Pharma does not sell or supply APIs or finished dosage products to individual patients, doctors, or pharmacies.

Questions? Call our customer API support number 1-(800)-881-8210

Product Name:
CAS Number:
For use as adjunctive treatment of partial seizures in adults with epilepsy.
Mode of Action:

Zonisamide binds to sodium channels and voltage sensitive calcium channels, which suppresses neuronal depolarization and hypersynchronization. Zonisamide also inhibits carbonic anhydrase to a weaker extent, but such an effect is not thought to contribute substantially to the drug's anticonvulsant activity.


Zonisamide is an antiseizure drug chemically classified as a sulfonamide and unrelated to other antiseizure agents. The precise mechanism by which zonisamide exerts its antiseizure effect is unknown, although it is believed that the drug blocks sodium and calcium channels, which leads to the suppression of neuronal hypersynchronization (i.e. convulsions). Sonisamide has also been found to potentiate dopaminergic and serotonergic neurotransmission but does not appear to potentiate syanptic activity by GABA (gamma amino butyric acid).


Primarily hepatic through cytochrome P450 isoenzyme 3A4 (CYP3A4). Undergoes acetylation and reduction, forming N-acetyl zonisamide, and the open-ring metabolite 2_sulfamoylacetyl phenol, respectively.


Symptoms of overdose include diminished breathing, loss of consciousness, low blood pressure, and slow heartbeat.

1, 2-benzoxazol-3-ylmethanesulfonamide
DB00909 (APRD00004)
Molecular Mass:
Zonisamida [Spanish] Zonisamidum [Latin]
General Reference:
General Reference:

  1. Murata M, Horiuchi E, Kanazawa I: Zonisamide has beneficial effects on Parkinsonês disease patients. Neurosci Res. 2001 Dec;41(4):397-9. Pubmed
  2. Gadde KM, Franciscy DM, Wagner HR 2nd, Krishnan KR: Zonisamide for weight loss in obese adults: a randomized controlled trial. JAMA. 2003 Apr 9;289(14):1820-5. Pubmed
  3. Hasegawa H: Utilization of zonisamide in patients with chronic pain or epilepsy refractory to other treatments: a retrospective, open label, uncontrolled study in a VA hospital. Curr Med Res Opin. 2004 May;20(5):577-80. Pubmed
  4. Leppik IE: Zonisamide: chemistry, mechanism of action, and pharmacokinetics. Seizure. 2004 Dec;13 Suppl 1:S5-9; discussion S10. Pubmed
  5. Ueda Y, Doi T, Tokumaru J, Willmore LJ: Effect of zonisamide on molecular regulation of glutamate and GABA transporter proteins during epileptogenesis in rats with hippocampal seizures. Brain Res Mol Brain Res. 2003 Aug 19;116(1-2):1-6. Pubmed
  6. Farooq MU, Moore PW, Bhatt A, Aburashed R, Kassab MY: Therapeutic role of zonisamide in neuropsychiatric disorders. Mini Rev Med Chem. 2008 Sep;8(10):968-75. Pubmed
  7. Schulze-Bonhage A: Zonisamide in the treatment of epilepsy. Expert Opin Pharmacother. 2010 Jan;11(1):115-26. Pubmed
  8. Kothare SV, Kaleyias J: Zonisamide: review of pharmacology, clinical efficacy, tolerability, and safety. Expert Opin Drug Metab Toxicol. 2008 Apr;4(4):493-506. Pubmed
  9. Peters DH, Sorkin EM: Zonisamide. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in epilepsy. Drugs. 1993 May;45(5):760-87. Pubmed
  10. Sobieszek G, Borowicz KK, Kimber-Trojnar Z, Malek R, Piskorska B, Czuczwar SJ: Zonisamide: a new antiepileptic drug. Pol J Pharmacol. 2003 Sep-Oct;55(5):683-9. Pubmed

Products currently covered by valid US Patents are offered for R&D use in accordance with 35 USC 271(e)+A13(1). Any patent infringement and resulting liability is solely at buyer risk.

LGM currently offers Monoclonal Antibodies (mAbs) for non-GMP/R&D use. Please inquire about Monoclonal Antibodies produced under GMP conditions.

Questions? Call our customer API support number 1-(800)-881-8210. 

Ask us about this product

API’s From Quality Manufacturers:

  • Streamlined API supply towards initial research stages as well as larger quantities of cGMP material for clinical trials and product commercialization
  • Premium quality GMP certified and fully accredited API manufacturing plants
  • Technical packages as well as access to filed DMF, ASMF or CEP (subject to availability)
  • Regulatory and technical assistance towards any submission type based on specific customer requirements

Find an API Product

Generic filters