They include veratridine, cyclopamine, and jervine. Other toxins that bind to this region include the alkaloids veratridine, batrachotoxin and aconitine. The structure of veratridine has been confirmed by NMR spectroscopy and X-ray crystallography. Veratridine acts a neurotoxin by increasing nerve excitability. Veratridine increases nerve excitability and intracellular Ca concentrations. Veratridine is readily absorbed through the skin and mucous membranes and through ingestion.