alpha-N-methyl-histamine is a metabolite of histamine that plays an important role in several (patho) physiological processes. alpha-N-methyl-histamine is being a potent agonist of histamine H3 receptor can be used as an effective therapeutic alternative in migraine patients.

PNU-109291 is a potent and selective 5HT1D receptor agonist. PNU-109291 was able to block neurogenic inflammation in the guinea pig model of migraine.

LY-334370 is a selective agonist at the serotonin 1F receptor. Lilly had been conducting phase II clinical testing of this compound in Europe as a potential therapy for migraine headaches. Lilly has now announced that it has discontinued commercial development of LY 334370 as a result of a review of data from an ongoing animal toxicology study. It was reported that the compound causes G-protein activation that is mediated by 5-HT1A receptors.

RS-127445 is a selective; high affinity; orally bioavailable serotonin 5-HT2B receptor antagonist. RS-127445 was found to have a nanomolar affinity for the 5-HT2B receptor (pKi = 9.5 /-0.1) and 1,000 fold selectivity for this receptor as compared to numerous other receptors and ion channel binding sites. RS-127445 potently antagonized 5-HT-evoked formation of inositol phosphates (pK(B) = 9.5 /-0.1) and 5-HT-evoked increases in intracellular calcium (pIC50 = 10.4 /-0.1). RS-127445 also blocked 5-HT-evoked contraction of rat isolated stomach fundus (pA2 = 9.5 /-1.1) and ( /-)alpha-methyl-5-HT-mediated relaxation of the rat jugular vein (pA2 = 9.9 /-0.3). RS-127445 (MT-500) was being developed for the prophylactic treatment of migraine. POZEN acquired MT-500 from Roche in November 1999 and assumed full responsibility for its development for migraine prophylaxis.

Rofecoxib is a nonsteroidal anti-inflammatory drug which selectively inhibits COX-2 and subsequent prostaglandin synthesis. The drug was developed by Merk and approved by FDA in 1999 for relief of signs and symptoms of arthritis, acute pain in adults, and painful menstrual cycles under the name Vioxx. Later on Merck voluntarily withdrawn Vioxx from the market due to safety concerns (high risk of heart attack and stroke).

Isometheptene (usually as isometheptene mucate) is a sympathomimetic amine sometimes used in the treatment of migraines and tension headaches due to its vasoconstricting properties. Isometheptene's vasoconstricting properties arise through activation of the sympathetic nervous system via epinephrine and norepinephrine. These compounds elicit smooth muscle activation leading to vasoconstriction by interacting with cell surface adrenergic receptors.

Cloxyquin has being shown to be a novel activator of the two-pore domain potassium channel TRESK, which is linked to causing migraines and controls the sensitivity of pain nerves in the brain.

Ginkgolide B belongs to the class of organic compounds known as ginkgolides and bilobalides. These are diterpene lactones with a structure based either on the gingkolide or the bilobalide skeleton. The ginkgolide skeleton is a very rigid structure consisting of hexacyclic C20 trilactone. The cis-fused F/A/D/C ring junction forms an empty semi-ball hole, the D ring contains a cage form tetrahydrofuran ring which occupies the center of the empty hole, and the oxygen atoms of the D,C and F ring and 10-hydroxyl group consist of an analogous crown ether structure. Ginkgolide B is one of the ginkgolides isolated from the leaves of the Ginkgo biloba tree. The Ginkgolide B is the most potent antagonist of platelet activating factor (PAF) and exhibits therapeutic action in a variety of diseases mainly by the PAF receptor. The ginkgolide B possesses a number of beneficial effects such as anti-inflammatory, anti-allergic, antioxidant, and neuroprotective effects. It promotes the proliferation, migration and adhesion of endothelial progenitor cells, and the induction of angiogenesis through vascular endothelial factor (VEGF). Ginkgolide B is considered a valid non-pharmacological (or nutraceutical) approach to the prophylaxis of both migraine with and without aura. Effects of ginkgolide B include reduction of Ca2+-stimulated intracellular events, scavenging of free radicals, modulation of central nervous system glutamatergic transmission and reduction of antiplatelet activating factor (PAF) levels in brain. Ginkgolide B is an active component of EGb, a standardised extract of Ginkgo biloba leaves. Ginkgolide B is one of the major components of EGb-761.

L-acetylcarnitine or acet-L-carnitine, a compound, naturally produced by the body, is necessary for fatty-acid metabolism and energy production. It is often taken as a dietary supplement. The mechanisms of action of acetylcarnitine have not been fully elucidated, but it seems that the main role of acetylcarnitine is to donate an acetyl group during fatty acid metabolism to help transport fatty acids, such as acetyl CoA, into the mitochondrial matrix where fatty acid metabolism occurs. L-acetylcarnitine is an investigational drug, which is approved in some countries, for example in Italy for diabetic neuropathy. Phase IV of clinical trials have revealed, that it also effective agent to treat the Alzheimer's disease. In contrary, the efficacy of L-acetylcarnitine as a prophylaxis in migraine patients did not provide evidence of benefit for efficacy. Besides, Acetyl-L-carnitine was in clinical trial Phase III to investigate its efficacy in the treatment of peripheral sensory neuropathy that anti-cancer chemotherapeutics induce. Recently published article unexpectedly discovered that this drug increased chemotherapy-induced peripheral neuropathy in a randomized trial.

Lomerizine (INN) (also known as KB-2796) is a diphenylpiperazine class L-type and T-type calcium channel blocker with relatively selective CNS effects. Voltage dependent L-type Ca2+ channels play an important role Ca2+ influx. L-type calcium currents typically require a strong depolarization for activation and are long-lasting. The common pharmacological profile of L-type channels is determined by the α1 subunit, which forms the Ca2+ selective. Lomerizine was developed as a potential agent for the selective improvement of the ocular or cerebrovascular circulation with minimal adverse cardiovascular effects, and it is used as an anti- migraine drug. Lomerizine selectively relaxes smooth muscle cells by inhibiting L-type Ca2+ influx, thereby reducing tone and increasing blood flow in cerebral vessels. Lomerizine also shows neuroprotective effects against secondary degeneration resulting from injury in retinal ganglion cells. While some calcium-channel blockers, such as flunarizine, act on the dopaminergic system, lomerizine is ineffective in vivo at inhibiting the release of dopamine. However, it has been observed to weakly inhibit the binding of [3H]spiperone to D2 dopamine receptors in vitro. While researchers are unsure of the reason for this difference, one hypothesis is that the doses administered cannot reach a high enough concentration in the brain to affect D2 receptors.