Dihydroergotamine is a semisynthetic ergot alkaloid derived from ergotamine by replacing the double bond between positions 9 and 10 with a single bond. It exhibits weaker oxytocic and vasoconstrictor activity compared to ergotamine. Used as the methanesulfonic or tartaric acid salts, it treats migraine and orthostatic hypotension. It acts as a serotonergic agonist, non-narcotic analgesic, vasoconstrictor, dopamine agonist, and sympatholytic agent. It is an ergot alkaloid and a semisynthetic derivative.
