Migraine is a common and debilitating neurological condition, affecting over 1 billion people globally. Characterized by intense, pulsating headaches often accompanied by nausea, photophobia, and phonophobia, migraine can significantly impair quality of life and daily functioning. While pharmacological therapies such as triptans, NSAIDs, and preventive medications help many, a considerable percentage of patients either do not respond to medications or experience intolerable side effects. In this context, Vagus Nerve Stimulation (VNS) is gaining recognition as a safe, effective, and non-invasive neuromodulation therapy for both acute and preventive treatment of migraine.
Vagus Nerve Stimulation involves applying mild electrical impulses to the vagus nerve transcutaneously, known as VNS. This nerve plays a critical role in autonomic and central nervous system regulation, including areas involved in pain modulation, inflammation, and cortical excitability, all of which are central to migraine pathophysiology.
Several high-quality randomized controlled trials have evaluated the effects of non-invasive VNS (VNS) for migraine:
- Straube et al. (2015) demonstrated that 1 Hz auricular VNS significantly reduced headache days in chronic migraine patients compared to higher-frequency (25 Hz) stimulation. Over 3 months, patients using 1 Hz VNS had an average reduction of 7 headache days per month—more than double the reduction seen in the 25 Hz group.
- Tassorelli et al. (2018) – PRESTO Study, a large double-blind, sham-controlled trial, showed that VNS was effective in the acute treatment of migraine attacks. Patients receiving VNS had significantly higher pain freedom at 30 and 60 minutes post-stimulation compared to the sham group. The therapy was also well-tolerated, with minimal side effects reported.
- Silberstein et al. (2020) reviewed safety and efficacy data across multiple trials and concluded that VNS devices offer a drug-free, portable option that is particularly valuable for patients with frequent attacks or contraindications to medications.
Vagus Nerve Stimulation (VNS) is thought to modulate brain circuits involved in pain and sensory processing by:
- Activating the nucleus tractus solitarius, which influences the trigeminovascular system involved in migraine.
- Reducing cortical spreading depression, a process believed to trigger aura and migraine pain.
- Modulating levels of serotonin, norepinephrine, and GABA—neurotransmitters implicated in migraine mechanisms.
- Reducing inflammatory cytokines and improving autonomic balance.
Non-invasive VNS is safe and well-tolerated. The most common side effects include mild skin irritation, tingling, or transient discomfort at the stimulation site. No serious adverse events were reported in any of the reviewed studies.
Vagus Nerve Stimulation (VNS) may be particularly beneficial for:
- Patients with chronic migraine (≥15 headache days/month)
- Individuals with episodic migraine who cannot tolerate triptans or other medications
- Patients with medication overuse headache (MOH)
- Those seeking a non-drug, neuromodulatory alternative
Vagus Nerve Stimulation (VNS), particularly non-invasive forms such as auricular VNS, offers a promising and evidence-based approach to managing migraine. With demonstrated efficacy for both acute relief and preventive reduction of migraine days, VNS is a valuable addition to modern migraine therapy, especially for patients with treatment-resistant symptoms or drug intolerance.