Dihydroergotamine (DHE) is a semisynthetic, hydrogenated ergot alkaloid, synthesized by reducing an unsaturated bond in ergotamine. Dihydroergotamine was originally envisaged as an antihypertensive agent, but it was later shown to be highly effective in treating migraine. Dihydroergotamine was first used to treat migraine in 1945 by Horton, Peters, and Blumenthal at the Mayo Clinic. In 1986, Raskin and Callaham reconfirmed the effectiveness of DHE for both intermittent and intractable migraine. The use of DHE was reviewed by Scott in 1992. In 1997, a nasal spray version was approved for use in migraine. Dihydroergotamine is indicated for the acute treatment of migraine headaches with or without aura and the acute treatment of cluster headache episodes. Dihydroergotamine binds with high affinity to 5-HT1Dα and 5-HT1Dβ receptors. It also binds with high affinity to serotonin 5-HT1A, 5-HT2A, and 5-HT2C receptors, noradrenaline α2A, α2B and α, receptors, and dopamine D2L and D3 receptors. The therapeutic activity of dihydroergotamine in migraine is generally attributed to the agonist effect at 5-HT1D receptors. Two current theories have been proposed to explain the efficacy of 5-HT1D receptor agonists in migraine. One theory suggests that activation of 5-HT1D receptors located on intracranial blood vessels, including those on arterio-venous anastomoses, leads to vasoconstriction, which correlates with the relief of migraine headache. The alternative hypothesis suggests that activation of 5-HT1D receptors on sensory nerve endings of the trigeminal system results in the inhibition of proinflammatory neuropeptide release.

Caffeine is a methylxanthine alkaloid found in the seeds, nuts, or leaves of a number of plants native to South America and East Asia that is structurally related to adenosine and acts primarily as an adenosine receptor antagonist with psychotropic and anti-inflammatory activities. Upon ingestion, caffeine binds to adenosine receptors in the central nervous system (CNS), which inhibits adenosine binding. This inhibits the adenosine-mediated downregulation of CNS activity; thus, stimulating the activity of the medullary, vagal, vasomotor, and respiratory centers in the brain. The anti-inflammatory effects of caffeine are due the nonselective competitive inhibition of phosphodiesterases. Caffeine is used by mouth or rectally in combination with painkillers (such as aspirin and acetaminophen) and a chemical called ergotamine for treating migraineheadaches. It is also used with painkillers for simple headaches and preventing and treating headaches after epidural anesthesia. Caffeine creams are applied to the skin to reduce redness and itching in dermatitis. Healthcare providers sometimes give caffeine intravenously (by IV) for headache after epidural anesthesia, breathing problems in newborns, and to increase urine flow. In foods, caffeine is used as an ingredient in soft drinks, energy drinks, and other beverages.

Donitriptan hydrochloride (F 11356) was developed by Pierre Fabre as a brain penetrant 5-HT1B/1D agonist. Which inhibits capsaicin-induced external carotid vasodilation and produces selective carotid vasoconstriction in various animal species. In January 2001, donitriptan had completed phase I trials for migraine and was scheduled to enter phase II development, but before development in phase II, this drug was discontinued.

Filorexant (MK-6096) is a novel, structurally distinct dual orexin receptor antagonist, conclusively validates orexin signalling mechanism as a specific and effective target for the treatment of insomnia and potentially other disorders in which sleep/wake dysregulation occurs. Also, it is being investigated as a possible agent against diabetic neuropathies, major depressive disorder and for the a migraine prophylaxis. Detected adverse events are: sleep-onset paralysis, excessive daytime sleepiness. As of May 2015, filorexant is no longer listed on Merck's online development pipeline.

Tropanserin (MDL 72422) is a potent and selective 5-HT3 receptor antagonist. It was investigated as a drug for the treatment of migraine. MDL 72222 was shown to be an effective antimigraine agent in a double-blind placebo-controlled study.

MK-3207 represents the third CGRP receptor antagonist to display clinical efficacy in migraine trials. It is a potent CGRP receptor antagonist with IC50 and Ki of 0.12 nM and 0.022 nM, highly selective versus human AM1, AM2, CTR, and AMY3. MK-3207 had been in phase II clinical trials by Merck Sharp & Dohme for the treatment of migraine. But the company had discontinued the research due to asymptomatic liver test abnormalities in 2010.

Telcagepant (MK-0974) is a calcitonin gene-related peptide receptor antagonist. Merck & Co was developing telcagepant for the treatment of pain. Telcagepant is an extremely potent CGRP antagonist with a Ki = 0.77 (0.07 nM). Telcagepant showed efficacy against acute migraines; however, different patient populations may show more beneficial effects with telcagepant versus triptans. In the acute treatment of migraine, Telcagepant was found to have equal potency to rizatriptan and zolmitriptan in two Phase III clinical trials. Merck & Co has now terminated development of the drug.

Carabersat is an anticonvulsant devoid of cardiovascular side effects with minimal central nervous system adverse actions. Carabersat does not bind to ion channels, purinergic, aminergic, opioid and other peptidergic receptors. It selectively interacts with its own binding site, which is not yet elucidated. Carabersat has no effect on sodium channels, GABAergic or glutamate pathways. Carabersat had been in phase II clinical trials for the treatment of epilepsy. It has a potential action in preventing migraines because it acts through an inhibition of the cortical spreading depression trigeminal nerve-induced vasodilatation in cats. Its good therapeutic index and the markedly reduced neurological impairments could make it a useful agent for migraine prophylaxis pending efficacy parameters of controlled studies, which are underway.

Tezampanel, also known as LY 293558 and NGX-424, is a drug originally developed by Eli Lilly, which is a competitive antagonist of the AMPA and kainate subtypes of the ionotropic glutamate receptor family. Tezampanel was in phase II clinical trial for treatment migraine, but this study was discontinued. Also this drug has several others potential pharmacological actions, one of them is anxiety disorders

CP 135807 is a selective 5-HT1D receptor agonist. Preclinical development for migraine was proposed but no development report released. This compound is used for neuroscience research.