Zonisamide

Category: pharmacological

Aliases: Zonegran

Pharmacological Mechanism

Sulfonamide antiseizure — Na+ + T-type Ca²⁺ channel blocker, weak carbonic anhydrase inhibition. Adjunct for partial seizures + off-label migraine prophylaxis + weight-loss adjunct (Qsymia precursor mechanistic relative).

Half-Life (t½)

PO: 63h

Dosing Guidelines

• PO: Typical 200 mg (Range: 100–600 mg)

Target Organ Systems

• nervous
• immune-hematologic

Pathways It Modulates

• Carbonic anhydrase inhibitor paresthesia (inhibitor) — CA II (weaker than topiramate, plus Na/T-type Ca channels)
• Voltage-gated sodium channels (Nav1.x) (inhibitor) — Nav1.x + T-type Ca²⁺ + carbonic anhydrase

Chemical Identifiers

• PubChem CID: 5734
• Formula: C8H8N2O3S
• Molecular weight: 212.23 g/mol
• InChIKey: UBQNRHZMVUUOMG-UHFFFAOYSA-N
• SMILES: C1=CC=C2C(=C1)C(=NO2)CS(=O)(=O)N

References

• PMID 27007995
• PMID 15837316