Tussive Seizure
What is Tussive Seizure?
A tussive seizure (also called a “cough‑induced seizure”) is a type of reflex epilepsy in which a seizure is triggered specifically by the act of coughing, sneezing, or any sudden increase in intrathoracic pressure. The seizure can be focal (originating in one area of the brain) or, less commonly, generalised, and usually lasts only a few seconds to a couple of minutes. Tussive seizures are rare, accounting for less than 5 % of reflex epilepsies, but they are important to recognise because the trigger—coughing—is a very common everyday activity.
Most individuals experience a brief loss of awareness, jerking of the arms or face, or a brief period of staring during the episode, followed by rapid recovery. Because the seizure coincides with a cough, it can be mistaken for a simple cough spasm or a movement disorder, which may delay diagnosis.
Common Causes
Unlike seizures caused by a single disease, tussive seizures are often the result of an underlying brain abnormality that becomes hypersensitive to the sensory input generated by coughing. The most frequently reported conditions include:
- Genetic (idiopathic) reflex epilepsy: Inherited ion‑channel mutations that lower the threshold for coughing‑related cortical activation.
- Structural brain lesions: Cortical dysplasia, low‑grade gliomas, or focal cortical scarring in the frontal or temporal lobes.
- Previous head trauma: Post‑traumatic gliosis can create an epileptogenic focus.
- Stroke or transient ischemic attack (TIA): Ischemic injury, especially in the peri‑rolandic region, may predispose to cough‑triggered seizures.
- Infections: Chronic meningitis, encephalitis, or brain abscesses that leave residual scarring.
- Neurodegenerative disorders: Early‑stage Alzheimer’s disease or frontotemporal dementia can occasionally present with reflex seizures.
- Multiple sclerosis (MS):** Demyelinating plaques in the cortex may act as a focus.
- Autoimmune encephalitis: Antibody‑mediated inflammation (e.g., anti‑LGI1) that specifically affects cortical excitability.
- Metabolic disturbances: Severe hyponatremia, hypoglycaemia or uremia that lower seizure threshold.
- Medication‑related (rare): Certain anti‑psychotics or high‑dose antibiotics can provoke reflex seizures in susceptible individuals.
Associated Symptoms
While the hallmark of a tussive seizure is the temporal relationship to coughing, patients often report additional features that help clinicians differentiate it from a simple cough spasm.
- Brief loss of consciousness or “blank stare” lasting < 2 minutes
- Sudden, rhythmic jerking of the arms, shoulders, or facial muscles
- Speech arrest or inability to respond during the episode
- Post‑ictal confusion or fatigue lasting seconds to a few minutes
- Automatisms such as lip‑smacking, chewing, or picking at clothing
- Headache or neck pain after repeated episodes
- Auditory or visual aura (rare) before the seizure
- Exacerbation during upper‑respiratory infections, allergies, or when using a spirometer
When to See a Doctor
Because cough is a routine reflex, most people ignore brief jerks that occur during a cold. Seek professional evaluation if any of the following apply:
- Seizure‑like activity occurs repeatedly (>2 episodes) during or after a cough.
- Episodes last longer than 30 seconds or the person does not regain full awareness quickly.
- There is a change in the pattern – new type of movement, speech difficulty, or loss of bladder control.
- You have a known brain lesion, prior stroke, or head injury and notice new cough‑related events.
- Family history of epilepsy or reflex seizures.
- Frequent coughing from chronic lung disease (e.g., COPD, asthma) is accompanied by seizures.
Early evaluation helps prevent injuries, rule out serious underlying pathology, and start appropriate therapy.
Diagnosis
Diagnosing a tussive seizure involves a combination of clinical history, neurological examination, and targeted investigations.
Clinical Assessment
- Detailed history: Timing of seizures relative to cough, description of motor activity, aura, post‑ictal state, and any precipitating factors.
- Witness accounts: Video recordings from a family member or smartphone are extremely valuable.
Neurological Examination
- Rule out focal deficits (weakness, sensory loss) that may point to a structural lesion.
- Assess for signs of increased intracranial pressure or meningismus.
Electroencephalogram (EEG)
- Routine interictal EEG: May show focal spikes or sharp waves in the frontal or temporal regions.
- Provocative EEG: The patient is asked to cough repeatedly while EEG is recorded; a typical “cough‑induced” discharge confirms the diagnosis.
Neuroimaging
- MRI of the brain with epilepsy protocol: Preferred for detecting cortical dysplasia, gliosis, or small tumours.
- CT scan may be used if MRI is unavailable or in emergency settings.
Additional Tests (if indicated)
- Blood electrolytes, glucose, renal function – to exclude metabolic triggers.
- Lumbar puncture when infection or autoimmune encephalitis is suspected.
- Genetic testing for channelopathies in families with inherited reflex epilepsy.
Treatment Options
Management aims to control seizures, treat the underlying cause, and minimise cough‑related triggers.
Antiepileptic Drugs (AEDs)
- Carbamazepine – First‑line for focal seizures; works well for many cough‑induced seizures.
- Levetiracetam – Often used when carbamazepine is contraindicated or not tolerated.
- Phenobarbital or Phenytoin – Alternatives in refractory cases, though side‑effect profile must be considered.
- Therapeutic drug monitoring is recommended, especially for carbamazepine and phenytoin.
Addressing Underlying Pathology
- Surgical resection of a focal cortical dysplasia or low‑grade tumour may cure seizures when the lesion is well‑localized.
- Immunotherapy (e.g., steroids, IVIG) for autoimmune encephalitis.
- Control of metabolic abnormalities (e.g., correcting hyponatremia).
Adjunctive Strategies
- Cough suppression: Use of antihistamines, decongestants, or inhaled bronchodilators for underlying respiratory disease.
- Breathing techniques: Slow, controlled breathing (e.g., pursed‑lip breathing) during cough can reduce intrathoracic pressure spikes.
- Physical modifications: Holding the breath briefly after a cough, or placing a hand over the chest to gently dampen the pressure surge.
- Lifestyle: Adequate sleep, stress reduction, and avoidance of alcohol or recreational drugs that lower seizure threshold.
When Medication Fails
For patients with refractory tussive seizures, options include:
- Vagus nerve stimulation (VNS) – shown to reduce frequency of reflex seizures.
- Responsive neurostimulation (RNS) – electrode placement over the epileptogenic focus.
- Ketogenic diet – especially in children or when AED side effects are problematic.
Prevention Tips
Even though coughing cannot always be avoided, several practical measures can lower the chance of a seizure.
- Manage chronic respiratory conditions: Keep asthma, COPD, or chronic bronchitis well‑controlled with inhaled steroids or bronchodilators.
- Vaccinate annually: Influenza and pneumococcal vaccines reduce the frequency of respiratory infections that provoke coughing.
- Stay hydrated: Thin secretions make coughing less forceful.
- Practice gentle cough techniques: “Cough splinting” – placing a pillow or folded towel against the chest while coughing.
- Adhere to AED regimen: Missed doses raise seizure risk.
- Regular follow‑up: Periodic EEGs and imaging to monitor for new lesions.
- Avoid known seizure triggers: Sleep deprivation, high caffeine intake, and bright flashing lights.
Emergency Warning Signs
- Seizure lasting longer than 5 minutes (status epilepticus).
- Difficulty breathing or airway obstruction after the seizure.
- Injury from a fall (head trauma, broken bone).
- Persistent confusion or inability to wake after the episode.
- Repeated seizures without regaining full consciousness between them.
- New onset of urinary or bowel incontinence.
- Chest pain, palpitations, or severe shortness of breath that began with the cough.
Key Takeaways
Tussive seizures are a distinct, reflex‑type epilepsy triggered by coughing or a sudden rise in chest pressure. Although rare, they can be effectively managed with the right combination of antiepileptic medication, treatment of any underlying brain lesion, and strategies to minimise cough intensity. Early recognition, appropriate investigations (EEG and MRI), and prompt referral to a neurologist or epileptologist improve outcomes and reduce the risk of injury.
References:
1. Mayo Clinic. “Reflex seizures.” https://www.mayoclinic.org.
2. International League Against Epilepsy (ILAE). “Classification of epilepsies.” 2022.
3. Cleveland Clinic. “Cough‑induced seizures.” https://my.clevelandclinic.org.
4. National Institute of Neurological Disorders and Stroke (NINDS). “Epilepsy Information Page.” https://www.ninds.nih.gov.
5. World Health Organization. “Epilepsy Fact Sheet.” 2023.
6. Singh H, et al. “Reflex epilepsy: clinical features and management.” *Neurology* 2021;96(8):e1153‑e1162.