An electric shock in the head manifests as a brief, sharp sensation, sometimes compared to a lightning bolt passing through the skull. This phenomenon has a name in the English medical literature: brain zap. It is not a classic pain like tension headaches or migraines, but a pinpoint discharge, often described as a current running through the brain for a fraction of a second.
Brain zaps and antidepressant withdrawal: the most documented mechanism
The most frequently identified cause in the literature is related to SSRIs or SNRIs (fluoxetine, paroxetine, venlafaxine, among others). Brain zaps typically appear in the weeks following a dose reduction or abrupt cessation of treatment.
This medication-related link remains poorly explained in French-speaking popular content. Many patients consult thinking they have a serious neurological problem, while the management primarily relies on a sensation of electric shock in the head often related to a revision of the dosage rather than heavy imaging tests.
The current recommendation is clear: anyone experiencing these shocks after a change in antidepressant should inform their prescribing doctor. A gradual adjustment of the dosage is sufficient in most cases to make the symptom disappear.
Arnold’s neuralgia and trigeminal neuralgia: when the nerve is involved
Electric shocks in the head are not always related to medication. Two neuralgias cause very similar pains, with a location that allows them to be differentiated.
Arnold’s neuralgia
The Arnold nerve (greater occipital nerve) originates in the upper cervical area. Its irritation or compression generates lightning-like pain starting from the base of the skull, rising towards the top of the head, sometimes reaching the orbit. The pain often radiates into the neck and worsens with rotational movements.
People who work for long periods in a seated position with their heads bent forward are particularly exposed. Treatment relies on targeted infiltrations, cervical physiotherapy, and sometimes antiepileptic medications used for their action on neuropathic pain.
Trigeminal neuralgia
The trigeminal nerve innervates the face. Its neuralgia causes shooting pains, usually unilateral, in the jaw, cheek, or forehead. These attacks last a few seconds but their intensity is described as among the most violent that exist.
Unlike Arnold’s neuralgia, trigeminal neuralgia is often triggered by innocuous actions: chewing, talking, washing the face. The diagnosis relies on a precise description of the symptoms and an MRI to rule out vascular compression of the nerve.
- Arnold’s neuralgia: pain starting from the neck to the top of the skull, worsened by cervical movements
- Trigeminal neuralgia: shock in the face (cheek, jaw, forehead), triggered by touch or chewing
- Medication-related brain zaps: brief and diffuse sensation throughout the skull, often with eye movement, related to a change in treatment
Long COVID and central pain dysregulation
Since 2022, cohorts of patients with long COVID report sensations of electric currents in the skull. These manifestations are among the functional neurological symptoms that persist for months after the initial infection.
The suspected mechanism is hypersensitization of the central nervous system. The brain interprets normal signals as painful, producing these shocks without identifiable nerve damage. This phenomenon of central pain dysregulation is also found in other post-viral syndromes.
Management differs radically from that of classic neuralgias. Standard painkillers are not very effective. The focus is on neuro-functional rehabilitation programs, combining progressive physical exercise, stress management techniques, and sometimes non-invasive neurostimulation.
Small fiber neuropathy: an underdiagnosed avenue
Recent research highlights the role of small fiber neuropathy in sensations of electric shock. These very small caliber nerve fibers transmit pain and thermal sensations. Their damage produces atypical symptoms that standard neurological examinations (EMG, conduction velocities) do not detect.
The diagnosis requires a skin biopsy to measure the density of intraepidermal nerve fibers. This test remains rarely prescribed in routine practice, which explains why many patients experiencing cranial electric shocks wander for a long time without a diagnosis.
When to consult a doctor for electric shocks in the head
Any recurrent cranial electric shock justifies a medical consultation. The doctor primarily looks for three avenues: a link with a recently modified medication, a neuralgia identifiable by its topography, or a post-infectious context.
- Consult urgently if the shock is accompanied by loss of strength in a limb, vision problems, or speech difficulties
- Consult within the week if episodes occur several times a day or disrupt sleep
- Always mention any recent changes in antidepressant treatment, even if they date back several weeks
- Report a history of COVID or recent viral infection if the shocks appeared in the following months
The diagnostic process generally begins with a clinical examination and a detailed interview. Brain MRI is not systematic but is necessary if the doctor suspects nerve compression or a demyelinating disease like multiple sclerosis, where the Lhermitte sign (electric shock during neck flexion) is a classic symptom.
The majority of cranial electric shocks find an identifiable explanation and respond to appropriate management. The main pitfall remains multiplying costly examinations before ruling out the most common cause: a simple medication adjustment.