Body zaps are sudden, brief, internal sensory experiences described as electric shock-like sensations, jolts, or shivers. While commonly felt in the head, they can radiate throughout the body, to the arms or spine. Many find them disorienting or startling, though generally not painful. They can interfere with daily activities and disrupt sleep.
Medication Withdrawal
Medication withdrawal is a primary cause of body zaps, especially when discontinuing psychiatric medications such as selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs). Their sudden absence or reduction can disrupt neurotransmitter balance, leading to antidepressant discontinuation syndrome (ADS).
SSRIs and SNRIs influence serotonin and norepinephrine levels in the brain. Serotonin regulates mood and sensory processing; norepinephrine, alertness and arousal. Abruptly stopping them rapidly changes brain neurochemistry, causing a rebound effect. This shift can result in neuronal hyperexcitability and altered sensory signaling, manifesting as electric shock sensations.
Zaps result from disruptions to ion channels and the brain’s serotonin-gating system, which filters sensory signals. Without accustomed medication levels, these systems become overly reactive. This excitability can be triggered by sudden movements like turning the head or eyes.
Beyond antidepressants, benzodiazepines are another medication class linked to body zaps during withdrawal. Benzodiazepines enhance gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter calming nerves. Abrupt discontinuation can lead to nervous system hyperexcitability, contributing to electric shock sensations. This withdrawal can also induce a protracted syndrome, with symptoms persisting for months or even years.
Antidepressant or benzodiazepine discontinuation syndrome symptoms emerge within two to four days after stopping or significantly reducing medication. They can last weeks to months as the brain gradually re-adjusts. Slowly tapering medication under medical supervision can minimize body zaps and other withdrawal symptoms.
Other Contributing Factors
While medication withdrawal is common, other factors also contribute to body zaps. Stress and anxiety are linked to these sensations. Chronic stress can lead to nervous system hyperexcitability, causing neurons to fire more sporadically. This heightened sensitivity can manifest as sudden jolts or buzzing sensations, especially in individuals prone to anxiety disorders.
Severe sleep deprivation can also induce or exacerbate body zaps. Sleep is essential for brain regulation; lack of rest can disrupt normal functioning, leading to sensory disturbances. Some individuals experience sensations similar to body zaps during hypnic jerks (sudden muscle contractions that occur as one falls asleep).
Nutritional deficiencies may contribute to nerve-related sensations, including electric shock-like feelings. For example, vitamin B12 deficiency can result in nerve damage. This deficiency can cause neurological symptoms like numbness, tingling, or electric sensations.
Body zaps can signal neurological conditions or nerve injuries. Spinal cord conditions (e.g., cervical spine issues, compression, inflammation, demyelination) can lead to electric shock sensations. Lhermitte’s sign, for example, is a neurological sign characterized by an electric shock sensation traveling down the spine and limbs when the neck is flexed, associated with multiple sclerosis or vitamin B12 deficiency.
Knowing When to Seek Medical Attention
While body zaps are a benign symptom of medication adjustment, consult a healthcare professional if severe, persistent, or significantly interfering with daily life. This includes highly disruptive, frequent, or extended sensations.
A medical evaluation is recommended if body zaps appear alongside other concerning symptoms. These might include:
New or worsening numbness
Muscle weakness
Changes in vision
Severe dizziness
Disorienting episodes
Difficulty with balance and coordination
Such symptoms could suggest an underlying neurological issue requiring prompt diagnosis and treatment.
Consult a doctor if body zaps emerge without a clear trigger (e.g., medication changes) or obvious explanation (e.g., stress, sleep deprivation). A healthcare provider can determine the cause and rule out serious conditions. Professional medical advice is essential for proper management.