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Seizures in Lewy Body Dementia: What to Watch For and How to Respond

Seizures can occur in Lewy body dementia (LBD) and are often missed because they may look like behavioral or cognitive changes rather than the classic convulsions we picture. This article explains why seizures happen in LBD, the subtle forms they can take, and gives you concrete, step-by-step guidance on what to do if you suspect your loved one is having seizure activity. You are not alone in this—there are clear things you can try to keep your person safe and comfortable.

Key points

  • Seizures in Lewy body dementia are often subtle—look for sudden emotional changes, blank stares, or confusion, not just convulsions.
  • Always time a seizure; call 911 if it lasts more than 5 minutes or if the person stops breathing.
  • Do not restrain, put anything in the mouth, or give food/water immediately after a seizure.
  • Keep a detailed log of episodes and possible triggers (sleep, infection, medication changes) to share with the doctor.
  • Work with a neurologist to create a seizure action plan and consider medication review for drugs that lower the seizure threshold.
  • Educate all caregivers (family, facility staff) on what to watch for and how to respond safely.

Why Seizures Happen in Lewy Body Dementia

In Lewy body dementia, abnormal clumps of a protein called alpha-synuclein (Lewy bodies) build up in brain cells, damaging them over time. This damage can disrupt the normal electrical activity of the brain, making it more likely for a seizure to occur. While not every person with LBD will have seizures, the risk is higher than in some other dementias because the disease affects multiple brain regions, including those involved in movement, thinking, and emotion. The seizure threshold—the brain's ability to resist abnormal electrical firing—can be lowered by the ongoing cell damage, by sleep deprivation, by certain medications, or by infections like a urinary tract infection.

Why Seizures Are Often Missed in LBD

Seizures in LBD are frequently missed because they often do not look like the dramatic convulsions we associate with epilepsy. Instead, they may appear as a sudden, intense emotional outburst—rage, fear, or despair—that seems to come out of nowhere. This is called a focal (or partial) seizure, originating in one area of the brain, such as the temporal lobe. The person may have an aura (a strange feeling or sensation) just before, but they cannot describe it. Caregivers may mistake these episodes for a behavioral symptom of dementia, like agitation or a mood swing, and not realize it is a seizure. Other times, a seizure may cause a brief blank stare, a period of confusion, or a repetitive movement like lip-smacking or picking at clothes. Because these symptoms overlap with common dementia behaviors, they are easily overlooked.

What Types of Seizures Can Occur in LBD

The most common seizure types in LBD are focal seizures (starting in one part of the brain) and generalized seizures (involving both sides of the brain). Focal seizures can be simple (no loss of consciousness) or complex (impaired awareness). A simple focal seizure might cause a strange taste, a rising feeling in the stomach, or a sudden intense emotion. A complex focal seizure can cause confusion, staring, or automatic movements like chewing or wandering. If the seizure spreads to both sides of the brain, it can become a generalized tonic-clonic seizure (formerly called grand mal), with stiffening and jerking of the body. However, this dramatic type is less common in LBD than the subtle focal seizures. The key is to watch for any sudden, unexplained change in behavior, emotion, or awareness that is out of character for your person.

General caregiving information, not medical advice. Check medications and major care changes with your clinician.

Step-by-step

  1. Stay calm, ensure safety, and note the start time — gently guide your loved one away from stairs, sharp edges, or hot surfaces, cushion their head with a pillow or folded jacket, and turn them on their side if safe; do not restrain them or put anything in their mouth.

  2. Call 911 if the seizure lasts longer than 5 minutes, if another seizure begins before they recover, or if they stop breathing, turn blue, or are injured.

  3. Provide calm, reassuring post-seizure care — they may be confused, sleepy, or agitated for minutes to hours; speak softly with phrases like 'You are safe. I am here with you. Take your time,' avoid peppering them with questions, and do not rush to reorient them.

  4. Document the event — write down the date, time, duration, what you saw before, during, and after, and any possible triggers (missed medication, poor sleep, fever, infection, stress, new drug); keep a longer diary of sleep, mood, and illness to spot patterns.

  5. Contact the doctor within 24 hours of a first-time seizure or any change in seizure pattern — describe what you saw, share your log, and ask whether an EEG or brain imaging is needed; do not change any medication on your own.

  6. Review every medication and supplement with the pharmacist or doctor — some antipsychotics, antidepressants, bupropion (Wellbutrin), tramadol, certain antihistamines, and high doses of donepezil can lower the seizure threshold; no drug should be stopped without medical guidance.

  7. Create a written seizure action plan with the doctor (when to give rescue medication if prescribed, when to call 911, who to contact) and share it with every caregiver, teaching them what to watch for, such as 'If Mom suddenly stares or seems scared for no reason, time it and call me.'

What not to do

  • Do not restrain the person during a seizure — restraint can injure you both; instead clear the area of dangers and stay nearby.

  • Do not put anything in their mouth, including your fingers, a spoon, or a cloth — people cannot swallow their tongue, and objects can break teeth or cause choking.

  • Do not assume it is just a behavioral symptom of dementia — if the behavior is sudden, intense, and out of character, especially with a blank stare or unexplained fear or rage, consider seizure, document it, and bring it to the doctor.

  • Do not give them water or food right after a seizure — they may not be fully alert and could choke; wait until they are clearly awake and aware before offering a sip.

  • Do not stop or change anti-seizure medications without consulting the doctor — abrupt changes can trigger more, sometimes more dangerous, seizures.

Practical tools

  • Seizure Observation Log

    A notebook or phone notes app to record each episode: date, time, duration, possible trigger, what you saw during (movements, emotions, awareness level), and post-seizure state. Add columns for daily sleep, mood, and illness (fever, UTI symptoms) to reveal patterns over weeks.

  • Calming Phrases for After a Seizure

    Use these in a soft, slow voice: 'You are safe now.' 'I am right here with you.' 'Take your time, no rush.' 'Let's just breathe together.' Avoid asking 'What happened?' or 'Do you remember?' right away, as these deepen confusion.

  • Home Safety Setup Checklist

    Pad sharp furniture corners, install nightlights in hallways and bathrooms, keep walking paths clear of clutter, consider a low bed or mattress on the floor if falls are a risk, and place a phone charger in every room so you can call for help without leaving your loved one's side.

  • Seizure First Aid Card

    A wallet-sized card that reads: 'I have Lewy body dementia and may have seizures. If I have a seizure: time it, do not restrain me, do not put anything in my mouth, turn me on my side if safe, call 911 if it lasts longer than 5 minutes or if I stop breathing.' Keep one in their wallet and give copies to all caregivers, neighbors, and program staff.

  • Medication Review Checklist

    A current list of all prescriptions, over-the-counter drugs, and supplements, brought to the doctor or pharmacist with the question: 'Could any of these lower the seizure threshold?' Common culprits in LBD include bupropion (Wellbutrin), tramadol, certain antipsychotics and antidepressants, some antihistamines, and high doses of donepezil. Never stop a drug on your own.

Discuss with your clinician

Ask the doctor: 'Could my loved one's sudden emotional outbursts or blank stares be focal seizures? Should we consider an EEG (even a routine one or a longer ambulatory EEG)?'

Ask the neurologist: 'What is the risk of starting an anti-seizure medication? Which one is safest for someone with Lewy body dementia?'

Ask the pharmacist: 'Please review all medications and supplements for anything that might lower the seizure threshold. Are there any interactions I should know about?'

Ask the doctor: 'If a seizure lasts more than 5 minutes, should we have a rescue medication at home? If so, what kind and how do I use it?'

Ask the neurologist: 'Should we do any brain imaging (MRI or CT) to look for other causes of seizures, like a small stroke or tumor?'

Ask the doctor: 'Are there any lifestyle changes (like improving sleep or treating a UTI) that could reduce seizure frequency without medication?'

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