DHE-45 (dihydroergotamine mesylate), an injectable migraine abortive, is currently in short supply and is on back order at all three labs who make the drug. It looks like the soonest the drug will be available is the end of February, though two of the three manufacturers have given no estimate of it’s return.
Migraine Medications — DHE 45 Injection Shortage from Ellen Schankenberg gives all the details.
If you rely on DHE, call your pharmacy to see if you can scoop up what remains in stock and contact your doctor for alternative medications. Migranal, the nasal spray of dihydroergotamine mesylate, may be an effective alternative.