Identification of tiagabine degradation products using liquid chromatography with electrospray ionization multistage mass spectrometry and ultra-performance liquid chromatography/high-resolution mass spectrometry.

Rationale: Tiagabine hydrochloride monohydrate drug substance (TGB) is an antiepileptic agent effective in the treatment of seizure disorders. The stability of TGB was studied and its degradation products were identified for the first time.

Methods: TGB was heated in the presence of H(2)O(2).