About the API
Dihydroergotamine mesilate, an ergot alkaloid, is indicated for the acute treatment of migraine headaches with or without aura and the acute treatment of cluster headache episodes. It can be administered orally as a tablet, injected or administered as a nasal spray.
The nasal spray is not intended for prophylactic therapy of migraine or for the management of hemiplegic or basilar migraine. Following intranasal administration, the mean bioavailability of dihydroergotamine mesilate is 32% relative to injectable administration.
Oral and injectable forms were approved by the FDA in 1946. In 1997, it was approved by the FDA as a nasal spray. Use via pulmonary inhalation has not yet been approved. It is a semi-synthetic form of ergotamine and was first synthesized from ergotamine in 1943. DHE is synthesized by hydrogenating an ergotamine produced naturally by the Claviceps purpurea fungus.