The short answer
Cushion the head, do not restrain, put nothing in the mouth, and note the time. CDC says call 911 for a first seizure, one over 5 minutes, no recovery between seizures, injury, or trouble breathing afterwards.
CDC first aid: ease the person to the floor, clear hard objects away, cushion the head, loosen tight clothing at the neck, and turn them gently onto one side with the mouth pointing to the ground.
Do not put anything in their mouth, including your fingers. No food or drink until they have fully recovered.
CDC says call 911 for a first seizure, one lasting more than 5 minutes if you do not know their usual length, no return to full consciousness, serious injury, or trouble breathing afterwards.
CDC adds pregnancy, a seizure in water, and diabetes with loss of consciousness to the 911 list.
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The full explanation.
The first minute
Unlike every other emergency on this site, this one asks something of whoever is standing there. These are CDC's steps, which are the ones to use in the United States:
- Ease them to the floor if they are not already down, and clear hard or sharp things out of the way.
- Turn them gently onto their side, with the mouth pointing towards the ground. This keeps the airway clear.
- Put something soft and flat under the head.
- Loosen anything tight around the neck, such as a collar or tie, so breathing is easier.
- Take off glasses.
- Stay with them until the seizure ends and they are fully awake, and talk calmly.
- Note the time the seizure starts and the time it finishes.
Most seizures end on their own. NHS says a seizure usually lasts a few seconds or minutes and stops by itself.
No clinician has reviewed this page yet. If a written seizure plan exists, that plan wins.
Three things not to do
Two of these are instincts, which is why they need saying.
Do not put anything in the mouth. NHS includes your fingers in that. The old idea about protecting the tongue causes broken teeth and bitten fingers, and nothing else.
Do not hold them down. CDC says do not hold the person down or try to stop their movements. Restraint can injure them and does not shorten the seizure.
Do not give food or drink until they have fully recovered. That includes water, and it includes tablets.
CDC adds one more: do not give mouth-to-mouth breaths during the seizure.
When to call an ambulance
This is the part worth knowing before it happens, because five minutes feels like an hour when you are watching.
CDC is the source to use in the United States. Call 911 if:
- The seizure lasts longer than 5 minutes.
- They have another seizure soon after the first one.
- They have trouble breathing or trouble waking up afterwards.
- They are injured during the seizure.
- The seizure happens in water.
- It is the person's first seizure.
- They have diabetes and lose consciousness.
- They are pregnant.
The UK's NHS list is close to the same, and adds two situations worth knowing:
- The seizure lasts longer than is usual for that person, even if under five minutes.
- They have had three or more seizures in 24 hours.
If you are ever unsure which rule applies, call. Nobody is criticised for calling 911 for a seizure.
Not every seizure needs an ambulance. NHS says people with epilepsy do not always need hospital, and usually have a care plan agreed with their doctors and family that says what to do, including when to give emergency medicine. If you know the plan and have been trained, follow it.
If they are in a wheelchair
NHS gives separate instructions, because tipping someone out of a chair does more harm than leaving them in it.
Put the brakes on. Leave any seatbelt or harness fastened. Support them gently and cushion the head. Do not try to move them out of the chair.
What to notice while it is happening
You are the only person who will see this. What you noticed shapes the treatment.
NHS suggests recording:
- What they were doing just before.
- Any unusual sensation they mentioned, such as an odd smell or taste.
- Whether there was any warning at all.
- Whether awareness or consciousness was lost.
- Any colour change. On brown or black skin this is easier to see on the palms, soles, lips, gums and inside the eyelids.
- Which parts of the body stiffened, jerked or twitched.
- Whether their breathing changed.
- Actions such as mumbling, wandering about, or fumbling with clothing.
- How long it lasted.
- Whether they lost control of the bladder or bowel, or bit their tongue.
- How they were afterwards, and whether they needed to sleep.
Typing that into a phone while you wait is more useful than trying to remember it in a corridor later.
Afterwards
People are often confused, exhausted or embarrassed. Stay. Say what happened, calmly, more than once if needed.
If the person was alone when it started, a fall or a burn may have happened that nobody saw. Check.
If this was a first seizure and you did not go to hospital, NHS says to ask for an urgent GP appointment or get help from NHS 111. In the United States, that is a same-day call to the oncology team or primary doctor.
Why this can happen during cancer care
Seizures are not only an epilepsy thing. NCI lists seizures among the symptoms of a brain tumor, alongside a morning headache or a headache that goes away after vomiting, and vision, hearing or speech problems.
NCI also notes that supportive care for brain tumors includes drugs to control seizures and to control fluid buildup or swelling in the brain. So a seizure during cancer care is something the team plans for, not something that catches them out.
A seizure does not by itself mean cancer has reached the brain. Only the treating team can work out the cause.
Related pages
Creating a Cancer Symptom and Call Plan, What to Have Ready for an Urgent Oncology Call, Preparing for an Emergency Department Visit With Cancer, and Airway Obstruction During Cancer Care.
Sources
Words to know
Tap any term to see what it means.
Common questions
What do I do in the first minute?
Use CDC's steps. Ease them to the floor and clear hard or sharp objects away. Turn them gently onto their side with the mouth pointing towards the ground, which keeps the airway clear; do this straight away rather than waiting for the shaking to stop. Put something soft and flat under the head, loosen anything tight around the neck, and take off glasses. Stay with them until they are fully awake, and note the time it starts and finishes.
Should I hold them still or protect their tongue?
No to both. NHS says do not put anything in their mouth, including your fingers. CDC says do not hold the person down or try to stop their movements, and do not give mouth-to-mouth breaths during the seizure. Neither source supports restraining anyone.
When does a seizure become an ambulance call?
Use CDC's list in the United States: the seizure lasts longer than 5 minutes; another seizure follows soon after the first; there is trouble breathing or waking afterwards; they are injured; it happens in water; it is a first seizure; they have diabetes and lose consciousness; or they are pregnant. Also call if the seizure lasts longer than is usual for that person, or if they have had three or more in 24 hours. When in doubt, call.
Does every seizure need hospital?
NHS says people with epilepsy do not always need an ambulance or hospital every time. They usually have a care plan agreed with their doctors and family or carers that says what to do, such as giving emergency medicine. If you have been trained and know the plan, you can follow it.
What should I write down afterwards?
NHS suggests noting what they were doing beforehand, any unusual sensation such as an odd smell or taste, whether there was warning, whether awareness was lost, any colour change, which parts of the body stiffened or jerked, breathing changes, how long it lasted, whether they lost bladder or bowel control, whether they bit their tongue, and how they were afterwards.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
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Your next step
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Sources last checked: 2026-08-11 what this meansLast updated: 2026-08-19Next planned review: 2027-01-22
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
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How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Editorial review complete — This page completed Cancer Explained's editorial checks (sources, safety, plain language, duplication). It has not been reviewed by a physician or other healthcare professional.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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