2970 T3D2928 Zonisamide Zonisamide is a sulfonamide anticonvulsant approved for use as an adjunctive therapy in adults with partial-onset seizures. Zonisamide may be a carbonic anhydrase inhibitor although this is not one of the primary mechanisms of action. Zonisamide may act by blocking repetitive firing of voltage-gated sodium channels leading to a reduction of T-type calcium channel currents, or by binding allosterically to GABA receptors. This latter action may inhibit the uptake of the inhibitory neurotransmitter GABA while enhancing the uptake of the excitatory neurotransmitter glutamate. 68291-97-4 5734 C8H8N2O3S 212.025560 White powder. 161-163°C 0.8 mg/mL Oral. Variable, yet relatively rapid rate of absorption with a time to peak concentration of 2.8-3.9 hours. Food has no effect on the bioavailability of zonisamide. 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. Primarily hepatic through cytochrome P450 isoenzyme 3A4 (CYP3A4). Undergoes acetylation and reduction, forming N-acetyl zonisamide, and the open-ring metabolite 2&ndash;sulfamoylacetyl phenol, respectively. Route of Elimination: Zonisamide is excreted primarily in urine as parent drug and as the glucuronide of a metabolite. Half Life: 63 hours No indication of carcinogenicity to humans (not listed by IARC). For use as adjunctive treatment of partial seizures in adults with epilepsy. May cause a potentially dangerous rash that may develop into Stevens Johnson syndrome, an extremely rare but potentially fatal skin disease. Symptoms of overdose include diminished breathing, loss of consciousness, low blood pressure, and slow heartbeat. No specific antidotes for Zonisamide overdosage are available. Following a suspected recent overdose, emesis should be induced or gastric lavage performed with the usual precautions to protect the airway. General supportive care is indicated, including frequent monitoring of vital signs and close observation. (L1712) 2009-07-21T20:27:56Z 2026-03-26T18:35:07Z Zonisamide C07504 10127 Zonisamide DB00909 ZON true NS(=O)(=O)CC1=NOC2=CC=CC=C12 C8H8N2O3S InChI=1S/C8H8N2O3S/c9-14(11,12)5-7-6-3-1-2-4-8(6)13-10-7/h1-4H,5H2,(H2,9,11,12) UBQNRHZMVUUOMG-UHFFFAOYSA-N 212.226 212.025562822 Exogenous Solid 0.5 HMDB15045 CHEMBL750 5532 <p>Tamar Nidam, &#8220;Novel sulfonation method for zonisamide intermediate in zonisamide synthesis and their novel crystal forms.&#8221; U.S. Patent US20030114682, issued June 19, 2003.</p> CHEM002300 DTXSID9046023 NS00000539 1,2-benzoxazol-3-ylmethanesulfonamide