Peptides for headache and migraine — beyond CGRP inhibitors

Migraine is not a headache problem. This distinction sounds semantic until you understand the biology, at which point it becomes the only framing that makes sense.

Migraine is a neurological disorder of the trigeminovascular system — the network connecting the trigeminal nerve, which supplies sensation to the face and head, with the blood vessels of the meninges that surround the brain. When a migraine attack is triggered, peptides are released from the peripheral terminals of the trigeminal nerve into the meningeal vasculature and the central nervous system. The most important of these, the one that has become the central target of modern migraine pharmacology, is calcitonin gene-related peptide — CGRP.

CGRP is a vasodilatory neuropeptide. During a migraine, CGRP levels in jugular venous blood rise sharply, and infusion of CGRP in migraine-susceptible individuals can reliably trigger an attack. This is not a correlation — it's a mechanistic link that took decades to establish and that now underpins an entire generation of migraine therapeutics. CGRP causes vasodilation in meningeal vessels, activates trigeminal sensory neurons, and participates in the central sensitization that makes the scalp tender and light unbearable during an attack. Understanding this explains why sumatriptan and the other triptans — which had been working clinically since the early 1990s without a fully understood mechanism — work the way they do: triptans constrict cranial blood vessels and block CGRP release from trigeminal neurons, hitting the same pathway from a different direction.

Cortical spreading depression is the correlate of migraine aura — a slow wave of neuronal depolarization followed by suppression that moves across the cortex at roughly three to five millimeters per minute. Aura symptoms map to which cortical region the wave passes through: visual cortex produces visual aura, sensorimotor cortex produces sensory symptoms. The spreading depression triggers the downstream activation of the trigeminovascular system, which is why aura typically precedes head pain rather than occurring simultaneously with it. Not everyone with migraine has aura, but the cortical excitability changes that enable spreading depression appear to be broadly present in the migraine brain even in those who never notice the visual phenomena.

PACAP — pituitary adenylate cyclase-activating polypeptide — is a second neuropeptide now understood to play a significant role in migraine. Like CGRP, PACAP levels rise during migraine attacks, and intravenous PACAP infusion triggers delayed migraine-like attacks in susceptible individuals. PACAP activates several receptor subtypes, and the PAC1 receptor in particular is now a target in the next wave of anti-migraine development. This matters because some patients who don't fully respond to CGRP-targeted therapy may have significant PACAP involvement in their attacks — and the two pathways, while overlapping, are distinct enough that targeting PACAP may reach patients that CGRP approaches don't.

The autonomic dimension of some migraine variants is worth naming. Cluster headache — often lumped with migraine in the popular imagination but a distinct and more severe condition — involves severe unilateral periorbital pain accompanied by prominent autonomic features: tearing, nasal congestion, eyelid drooping, sometimes facial sweating on the affected side. Attacks occur in clusters over weeks or months, often at the same time of day, then remit. The biology involves the trigeminal-autonomic reflex and likely hypothalamic involvement in setting the circadian timing. The treatment approach is different from migraine: high-flow oxygen and triptans for acute attacks, verapamil and sometimes lithium for prevention, and in refractory cases deeper interventions including sphenopalatine ganglion stimulation and occasionally ketamine-based approaches in specialist centers.

The conventional treatment landscape for migraine has changed more in the past decade than in the previous three combined.

For acute attacks, triptans remain effective and widely used — sumatriptan, rizatriptan, eletriptan, and others in the class work by agonizing 5-HT1B/1D receptors, constricting cranial vessels and inhibiting CGRP release. Their cardiovascular contraindication in patients with vascular disease limits their use in a subset of patients. Gepants — CGRP receptor antagonists — are now FDA-approved for acute treatment (rimegepant, ubrogepant) and have the advantage of no vasoconstriction, making them usable in patients for whom triptans are contraindicated. Lasmiditan, a selective 5-HT1F agonist, offers another acute option without vasoconstriction. NSAIDs and combination analgesics have a role in milder attacks. Opioids are avoided in migraine care as best practice — they worsen the condition over time through mechanisms involving medication overuse headache and central sensitization.

The preventive landscape has been transformed by CGRP. The four approved anti-CGRP monoclonal antibodies — erenumab, which targets the CGRP receptor; and fremanezumab, galcanezumab, and eptinezumab, which target CGRP itself — have produced clinically meaningful reductions in monthly migraine days for a substantial proportion of patients, with a tolerability profile substantially better than older preventives. For patients who had previously cycled through topiramate, propranolol, amitriptyline, valproate, and other older agents with inadequate results or side effects, the monoclonals represent a genuine category shift. Monthly or quarterly dosing by subcutaneous injection or IV infusion makes adherence more achievable than daily oral medications. These are not peptides in the compounding sense — they are FDA-approved biologics, and they represent the evidence-based standard of care for moderate-to-severe migraine that hasn't responded to acute treatment alone.

OnabotulinumtoxinA — Botox — is FDA-approved for chronic migraine (fifteen or more headache days per month), with a mechanism that includes inhibition of CGRP and substance P release from peripheral trigeminal afferents. The evidence base is solid for the chronic migraine indication.

Against that backdrop — a field with FDA-approved CGRP biologics, gepants, triptans, and Botox — what does the research-stage peptide landscape look like?

The honest answer is: limited and largely indirect.

The most direct peptide biology in migraine is already the approved therapy — the CGRP monoclonals are themselves biologics operating on a peptide target. The gepants are small molecule CGRP receptor antagonists. The conceptual contribution of peptide biology to migraine is enormous; the translation into novel peptide therapeutics beyond the established CGRP pathway is still underway.

The mitochondrial dimension of migraine has generated research interest because a subset of migraine patients show evidence of mitochondrial dysfunction — elevated lactate in cerebrospinal fluid and blood during attacks, response to mitochondrial nutrients, and overlap with migraine in conditions of known mitochondrial disease. Riboflavin (vitamin B2) at 400 mg daily has the strongest evidence among nutritional interventions for migraine prevention, with multiple randomized controlled trials showing modest but real reduction in attack frequency. Coenzyme Q10, also involved in mitochondrial electron transport, has supportive evidence at 100-300 mg daily. Magnesium deficiency is more common in migraine patients than in controls, and magnesium supplementation has evidence for prevention, particularly in menstrual migraine.

MOTS-c — a mitochondria-derived peptide involved in metabolic regulation and cellular stress response — has been studied in metabolic and exercise contexts. The connection to migraine is indirect: if mitochondrial dysfunction contributes to the neuronal excitability that characterizes the migraine brain, then mitochondria-supportive interventions become theoretically relevant. This is preclinical and speculative territory; MOTS-c has not been studied in migraine populations.

Selank, researched for its anxiolytic and stress-modulating properties, becomes relevant to migraine through a well-documented clinical overlap. Anxiety disorders are significantly comorbid with migraine — not coincidentally. Stress is among the most commonly reported migraine triggers, and the neurobiological links between HPA axis activation, CRF signaling, and trigeminovascular sensitization are real. In patients whose migraine pattern is tightly coupled to stress and anxiety — the headache that arrives after, not during, the stressful event, reflecting the cortisol withdrawal dynamic — addressing the anxiety-stress-HPA axis component is part of the migraine picture. Selank has been researched for anxiety modulation, and the connection to stress-triggered migraine is at least mechanistically coherent, though direct clinical evidence in migraine is not established.

BPC-157 enters the headache picture through the gut-headache connection that a subset of migraine patients experience. The gut-brain axis is real — the enteric nervous system shares neurotransmitter systems with the central nervous system, and migraine patients have higher rates of gastrointestinal symptoms, irritable bowel syndrome overlap, and gut motility changes. Nausea and vomiting during attacks reflect not just brainstem activation but a gut that's dysregulated in the context of the attack. BPC-157 has been researched for gut mucosal integrity and gut-brain signaling in animal models; whether this translates to meaningful migraine benefit in humans is not established, but in patients where the gut-migraine connection is prominent, gut-supportive approaches have a coherent rationale.

The honest framing for the peptide-migraine space requires directness: migraine is now a specialist-managed neurological condition with FDA-approved options that work for many patients. If you have chronic or episodic migraine and have not had a neurology evaluation, and specifically have not discussed the CGRP monoclonals with a provider, that evaluation and that conversation should come first. The CGRP era has produced real and substantial improvement for patients who had previously exhausted the older options. Exploring peptide approaches while bypassing the established neurology pathway is, for most migraine patients, working in the wrong order.

For patients who have worked through the conventional options and are looking at the margins — at the mitochondrial support component, at the stress-anxiety-HPA axis coupling, at the gut connection — a prescribing provider who understands both migraine biology and the research-stage peptide landscape can help map what adjunctive approaches might be reasonable to explore. Those explorations sit clearly downstream of the foundational work: identifying individual triggers with some rigor, medication overuse headache assessment (which chronically worsens migraine and is missed more often than it should be), sleep quality and consistency, hydration, hormonal evaluation in women where menstrual migraine suggests hormonal triggering, and optimizing the foundational nutritional interventions with actual evidence — magnesium, riboflavin, CoQ10.

The migraine brain is a specific kind of brain. More excitable than average. More sensitive to environmental and physiological perturbations. More susceptible to the cascade of trigeminovascular activation that produces the event. That specificity is not a character flaw or a weakness. It's a biological phenotype, increasingly well-characterized, with real mechanisms and a treatment landscape that has improved more in the past decade than anyone who suffered through the triptan era alone might have believed possible. What remains at the research edge, including the mitochondrial, the autonomic peptide, and the gut-brain connections, is worth understanding — but as a frame for informed conversation with a neurology specialist, not as a substitute for one.