<chemical> Dihydroergotoxine. A mixture of three different ergotaman-3',6',18-triones, dihydroergocornine, dihydroergocristine, and dihydroergocryptine. It has been proposed to be a neuroprotective agent and a nootropic agent. The mechanism of its therapeutic actions is not clear, but it can act as an alpha-adrenergic antagonist and a dopamin...