Pharma & Specialty Chemical Standards

Flunarizine (IUPAC name: 6-(2,3-dimethylphenyl)-2,3,4,5-tetrahydro-1,2-benzothiazepine; molecular formula C18H21N; molecular weight 251.37 g/mol) is a calcium channel blocker belonging to the 1,2-benzothiazepine class. Its structure features a fused benzothiazepine ring system with a dimethylphenyl substituent. Therapeutically used for migraine prevention and vertigo, it exhibits high lipophilicity and extensive plasma protein binding. Mechanistically, it inhibits voltage-gated calcium channels, reducing intracellular calcium influx and neuronal hyperexcitability. Its pharmacokinetics are characterized by low oral bioavailability due to first-pass metabolism and prolonged half-life.