Febrile Seizure in a Child: What to Do for 5 Minutes, and When to Call 119

Hello. I am Shunichi Gamo, MD, PhD, a board-certified pulmonologist and the director of Sendai Airport North Clinic.

When I see children at the fever clinic, some families rush in with pale faces, saying, “My child had a fever and just had a seizure at home.” Watching your own child’s eyes roll back and the body stiffen right in front of you is one of the most frightening sights there is.

To state the conclusion first, most febrile seizures in children stop within a few minutes and, in nearly all cases, leave no lasting effects. What I would like families to do is, roughly, “note the time, turn the child onto their side, put nothing in the mouth,” and then call 119 after 5 minutes. That is all.

In this article, I explain what febrile seizures are, what to do when a seizure happens, and when to see a doctor after it stops. I also sort out the chance of recurrence, fever reducers, diazepam suppositories, and the thinking on vaccination, following the 2023 guideline of the Japanese Society of Child Neurology. For how to judge a child’s fever at night or on holidays in general, please also see the related article at the end of this page.

Since October 4, 2026, we also run the fever clinic on Sundays and national holidays
10:00 to 15:00 (no lunch break). No reservation is needed; we accept patients by same-day check-in. PCR test results are given on the same day. On Sundays and national holidays we run only the fever clinic; we do not offer general outpatient care or IV drips. We are closed on Sunday, October 25, and from November we are generally open every Sunday and national holiday. Announcement about the Sunday and national holiday fever clinic

[Conclusion] When a seizure starts: “note the time, turn on the side, nothing in the mouth,” and call 119 at 5 minutes

First, here is what to do during a seizure. Please just remember the order.

The Japanese Society of Child Neurology and the Japan Epilepsy Society have published a response flowchart for families[1]. It, too, treats the basics as “lay the child down (on the side if they seem about to vomit),” “do not put anything in the mouth,” and “observe and record (a video is best)”[1].

And even after the seizure stops and the child is fully awake, the flowchart says to go on to see a medical institution[1]. It is not “it stopped, so let’s wait and see”; seeing a doctor even after it stops goes together with the rest.

What are febrile seizures? [common in Japanese children]

A febrile seizure is a seizure that occurs with a fever of 38℃ or higher, mainly in children from 6 months to 5 years (60 months) of age[2]. It refers to cases with no other clear cause, such as meningitis (an infection of the membranes that wrap the brain)[2].

According to the guideline, the frequency abroad is roughly 2 to 5% of children, but in Japan figures of 7 to 11% have been reported, and differences in race and environment are cited as the reason[2]. An older survey of 17,044 three-year-olds in Fuchu City, Tokyo, from 1974 to 1980 found 8.3%[3].

However, the guideline cautions that these figures are based on public health center checkups and statistics from a single facility. It also notes that a full survey in Tamano City, Okayama Prefecture, found a frequency of 3.4% up to age 5, about the same as in Europe and North America[2]. Either way, it is by no means rare.

What the guideline calls “the most important thing in care” is for families to understand that febrile seizures are basically a benign condition (one that does not threaten life or development)[2].

In a study in the United Kingdom that followed 14,676 people born in the same week of 1970 up to age 10, 398 children who had experienced febrile seizures were compared with other children[4]. (The analysis was of 381 children, after excluding those who already had developmental problems and the like[4].) Of 102 measures of schooling, intelligence, and behavior, only 4 differed, which is within the range of chance. Children who had recurrences had the same results as children who had only one[4].

Simple and complex types

A febrile seizure is called “complex” if any one of the following 3 applies, and “simple” if none applies[2].

The complex type was classified as a factor linked to later epilepsy, and compared with the simple type it calls for more tests and closer follow-up[2]. “Noting the time” and “taking a video” are directly tied to this assessment.

What to do when a seizure happens [call 119 after 5 minutes]

Why “5 minutes”?

The guideline uses a seizure lasting 5 minutes or more as the practical guide for “febrile status epilepticus,” the point at which you should consider starting treatment with a medicine to stop it[2]. The medicines that stop a seizure (an injection, or a medicine placed inside the cheek) are, as a rule, used at medical institutions, and ordinary homes do not have them.

So it is fine to call 119 after 5 minutes, without waiting for it to stop. Tell the ambulance crew, “A febrile seizure has lasted more than 5 minutes.”

Call 119: signs you must not wait on

If even one of the following applies, call 119 without hesitation.

The flowchart for families also says to call an ambulance if the child is not fully awake after the seizure stops[1]. If the child goes still and stops breathing, proceed to basic life support (such as chest compressions)[1].

[After it stops, be seen right away, even at night]

Even if the seizure stops within a few minutes, in the following cases please see a doctor without waiting for morning, even at night or on a holiday.

The guideline also treats disturbed consciousness lasting 30 minutes or more after a seizure, a stiff neck, and a bulging fontanelle as signs for suspecting meningitis and doing tests, and a poor general condition or dehydration as signs for considering hospital admission[2]. In babies under 1 year old, the signs of meningitis may not be clear, and this is an age at which doctors think about testing more carefully[2]. A seizure that differs between left and right is the complex type described earlier and needs to be assessed in a doctor’s exam[2].

[Consult #8000, then be seen the next morning]

If it is the second or later seizure, it stops within a few minutes, and consciousness and color return to normal right away, it is fine to consult #8000 (the children’s medical phone consultation line) and be seen the next morning. However, if you feel “something is different from before,” follow that instinct and see a doctor.

What to tell us when you see a doctor

Will it come back? Will it turn into epilepsy? [recurrence rate and related factors]

According to the guideline, the overall recurrence rate for febrile seizures is about 30%, and about 15% in children with no predictive factors for recurrence (markers of how likely it is to recur)[2]. More than half of children have only one in their lifetime.

In a US study that followed 428 children who had a first febrile seizure for 2 years or more, 31.8% had a recurrence[5]. 17.1% had one recurrence, 8.9% had two, and 5.8% had three or more[5].

The guideline lists the following 4 predictive factors for recurrence. If even one is present, the chance of recurrence is more than doubled[2].

In other words, children who have a seizure soon after the fever starts, while it is still not that high, are more likely to have a recurrence than children who have a seizure after the fever has become high.

What is the chance of developing epilepsy?

The chance of developing epilepsy (a condition with repeated seizures even without fever) is about 2.0 to 7.5% in children who have had febrile seizures[2]. It is true that this is higher than the 0.5 to 1% of children in general, but the guideline asks that families understand that more than 90% do not develop epilepsy[2].

The factors linked to epilepsy are 5: abnormal development or neurological findings, epilepsy in a parent or sibling, the complex type, a seizure within 1 hour of the fever, and onset at age 3 or later[2]. When none of the first 3 is present, epilepsy develops in 1%; with one, 2%; with two or three, 10%[2].

Can it be prevented? [fever reducers, diazepam suppositories, vaccination]

Fever reducers do not prevent recurrence

People tend to think, “If we bring the fever down, there won’t be a seizure,” but the guideline says that fever reducers have no effect in preventing a recurrence of febrile seizures, and using them to prevent recurrence is not recommended[2]. It also states clearly that there is no evidence that a rise in fever after a fever reducer wears off makes seizures more likely[2].

There is a randomized controlled trial that followed 231 children who had a first febrile seizure for 2 years at 5 hospitals in Finland[6]. In this kind of study, children are assigned by lottery to a medicine or a placebo (a medicine with no active ingredient) and compared. Recurrence was 23.4% in the group that used a fever reducer (diclofenac, ibuprofen, or acetaminophen) at each fever and 23.5% in the placebo group, with no difference[6].

However, this does not mean “do not use fever reducers.” The guideline also says that using a fever reducer to ease discomfort and make it easier to drink and sleep can be done just as for other feverish illnesses[2]. It is enough to remember that the purpose is “to make the child comfortable,” not “to prevent seizures.”

Diazepam suppositories (Diap) are at the doctor’s discretion

A diazepam suppository is a medicine placed in the rectum in advance when a fever develops, to prevent a seizure. There is a systematic review (a study that gathers all the studies of preventive drugs and evaluates them again) of 32 trials worldwide with 4,431 children[7]. With diazepam given during fever, recurrence at 6 months was reduced to 0.64 times that of placebo or no treatment[7]. The 95% confidence interval (the range within which the true value is thought to lie) is 0.48 to 0.85[7].

It certainly works. However, side effects such as drowsiness and unsteadiness[2] were recorded in up to 36% of children with drugs in the diazepam family[7]. From the standpoint that “febrile seizures are a benign condition,” the guideline too says it is not a medicine for everyone[2].

The guideline’s targets for preventive use are, roughly, one of the following two[2].

The 6 items are as follows[2].

• A seizure that starts in one part of the body, or a seizure that repeats within 24 hours
• Existing abnormal development or neurological findings
• Febrile seizures or epilepsy in a parent or sibling
• The first seizure was before 12 months of age
• A seizure less than 1 hour after the fever began
• A seizure with a fever below 38℃

The standard way to use it when prescribed is one suppository at about 37.5℃, and another 8 hours later if the fever continues[2]. When it is used together with a fever-reducing suppository, insert the diazepam first and leave at least 30 minutes between them[2]. However, the prescribing doctor’s instructions take priority on the temperature at which to insert it and whether to insert a second one. Please do not use a sibling’s suppository or leftovers from before on a child who has not been prescribed it, on your own judgment.

The length of time to continue is generally said to be 1 to 2 years after the last seizure, or until age 4 to 5, but there is no clear evidence, and it is decided in consultation with the child’s doctor[2]. Also, a suppository does not completely prevent seizures, so please keep an eye on your child for 1 to 2 days after using it[2].

Note too that drowsiness from a diazepam suppository can make it harder to tell meningitis or encephalopathy (a condition in which the brain swells and consciousness worsens) apart[2]. Please do not assume “he is dazed because of the suppository”; if something seems wrong, see a doctor.

Vaccinations can be given

The guideline says that children who have had febrile seizures may receive all current vaccinations[2]. As for timing too, as long as you pay attention to the child’s condition on the day, it says they may be given promptly regardless of how long it has been since the last seizure[2].

There is a study that followed 537,171 children born in Denmark from 1991 to 1998[8]. In the 2 weeks after the MMR (measles, mumps, rubella) vaccine, febrile seizures were 2.75 times more likely[8]. However, the increase in children aged 15 to 17 months was 1.56 per 1,000 children, and febrile seizures after the vaccine did not lead to more epilepsy[8].

In Japan, measles and rubella are given as the MR vaccine, but the thinking is the same. The guideline too says to vaccinate after explaining in advance the usefulness of the vaccine, the side effects that can occur, and what to do then[2]. When you are vaccinated, tell them “my child has had febrile seizures,” and simply keep in mind the period when fever tends to follow vaccination (within 2 weeks for live vaccines and within 1 week for inactivated vaccines in most cases[2]).

What we can do at our clinic [find the cause of the fever, and refer you to a hospital if needed]

While a seizure is still going on, call 119 without hesitation. An ambulance leads to treatment that stops the seizure faster than coming to our clinic.

After the seizure has stopped and your child has settled, if you want us to look for the cause of the fever, or want a proper exam the next morning, please come to our fever clinic. Our policy is not to turn away anyone seeking the fever clinic (depending on your symptoms, we may guide you to a more suitable medical institution). We also see fevers in small children.

If a complex type is suspected, or we judge that tests or hospital admission are needed, we will refer you to a hospital with a pediatrics department.

Day	Hours
Mon, Tue, Wed, Fri, Sat	9:00-12:00 / 14:00-18:00
Sundays and national holidays (from October 4, 2026)	10:00-15:00 (no lunch break, fever clinic only)
Thursday	Closed

On Sundays and national holidays, we are closed on Sunday, October 25, and from November we are generally open every Sunday and national holiday. For details, please see the announcement about the Sunday and national holiday fever clinic.

What happens during your visit (no reservation needed)

For the detailed steps, please see About the fever clinic pre-visit questionnaire and same-day check-in. Patients are generally seen in order of check-in, but the order may change depending on how severe the symptoms are.

Please also note that we cannot give IV drips on Sundays and national holidays. If your child is limp and cannot drink at all, or is otherwise likely to need an IV drip, go to a medical institution that can give IV drips.

Frequently asked questions (FAQ)

The seizure stopped after 2 minutes and my child is fine now. Do we still need to see a doctor?

Yes. If it was the first seizure, the child is under 1 year old, there was a difference between the left and right sides, or the child stays dazed for 30 minutes or more after it stops, please be seen right away, even at night. If it is the second or later seizure, it stopped within a few minutes, and consciousness and color returned right away, it is fine to consult #8000 and be seen the next morning. The flowchart for families also says to see a medical institution after the seizure stops.

Should I put something in the mouth during a seizure so the child doesn’t bite the tongue?

No, please do not. Putting in a finger or a towel can cause choking and injury, and can injure the person who put it in. Turn the face to the side so that vomit does not block the throat, note the time, and if you can, take a video. Please do not shake the child or hold the child down either.

If I give fever reducers often, can I prevent seizures?

No. The 2023 guideline says fever reducers have no effect in preventing recurrence and does not recommend using them for that purpose. In a trial that followed 231 children for 2 years, the recurrence rate was the same in the group that used fever reducers and the placebo group. However, it is fine to use fever reducers to ease discomfort.

If a child has a febrile seizure once, will they develop epilepsy?

Most children do not. According to the guideline, about 2.0 to 7.5% develop epilepsy after a febrile seizure, and more than 90% do not. The chance rises when there are factors such as abnormal development or neurological findings, epilepsy in a parent or sibling, or the complex type, so if any of these applies, please consult a pediatrician.

Should vaccinations be postponed for a child who has had a febrile seizure?

No. The guideline says all current vaccinations may be given, and, as long as you pay attention to the child’s condition on the day, they may be given regardless of how long it has been since the last seizure. It is enough to tell them about the febrile seizure when you are vaccinated and to be prepared for the period when fever tends to follow vaccination (within 2 weeks for live vaccines and within 1 week for inactivated vaccines).

Can I bring my child to your clinic on a Sunday or national holiday after a seizure?

While a seizure is still going on, call 119. For an exam of the fever after the seizure has stopped and your child has settled, please come to the Sunday and national holiday fever clinic (10:00 to 15:00). We are closed on Sunday, October 25, and from November we are generally open every Sunday and national holiday. No reservation is needed; we accept patients by same-day check-in. We cannot give IV drips on Sundays and national holidays.

Summary [for febrile seizures, remember “5 minutes” and “seeing a doctor afterward”]

No parent can stay calm when watching their own child have a seizure. Even so, please remember just these four things: “note the time, turn on the side, nothing in the mouth, 119 at 5 minutes.” The exam of the fever after it stops, and referral to a hospital, please leave to us.

That’s all.

Disclaimer

This article is intended to provide general medical information and does not replace an examination, diagnosis, or treatment by a doctor. The content is based on medical knowledge at the time of publication, but the appropriate response differs for each individual. If you are worried about your symptoms, please consult a medical institution.

References

1. Japanese Society of Child Neurology, Japan Epilepsy Society. Nationwide standard response manual for children’s seizures and clouded consciousness for families and non-medical people (flowchart for seizures and clouded consciousness) (in Japanese). Japanese Society of Child Neurology website. Published October 2024. https://www.childneuro.jp/about/7295/
2. Japanese Society of Child Neurology (supervision), Febrile Seizure Clinical Practice Guideline Revision Working Group (eds). Clinical Practice Guideline for Febrile Seizures 2023 (in Japanese). Shindan to Chiryosha. 2023. https://www.childneuro.jp/about/about-33
3. Tsuboi T. Epidemiology of febrile and afebrile convulsions in children in Japan. Neurology. 1984 Feb;34(2):175-81. doi:10.1212/wnl.34.2.175 PMID: 6538005
4. Verity CM, Greenwood R, Golding J. Long-term intellectual and behavioral outcomes of children with febrile convulsions. N Engl J Med. 1998 Jun;338(24):1723-8. doi:10.1056/NEJM199806113382403 PMID: 9624192
5. Berg AT, Shinnar S, Darefsky AS, Holford TR, Shapiro ED, Salomon ME, et al. Predictors of recurrent febrile seizures. A prospective cohort study. Arch Pediatr Adolesc Med. 1997 Apr;151(4):371-8. doi:10.1001/archpedi.1997.02170410045006 PMID: 9111436
6. Strengell T, Uhari M, Tarkka R, Uusimaa J, Alen R, Lautala P, et al. Antipyretic agents for preventing recurrences of febrile seizures: randomized controlled trial. Arch Pediatr Adolesc Med. 2009 Sep;163(9):799-804. doi:10.1001/archpediatrics.2009.137 PMID: 19736332
7. Offringa M, Newton R, Nevitt SJ, Vraka K. Prophylactic drug management for febrile seizures in children. Cochrane Database Syst Rev. 2021 Jun;6(6):CD003031. doi:10.1002/14651858.CD003031.pub4 PMID: 34131913
8. Vestergaard M, Hviid A, Madsen KM, Wohlfahrt J, Thorsen P, Schendel D, et al. MMR vaccination and febrile seizures: evaluation of susceptible subgroups and long-term prognosis. JAMA. 2004 Jul;292(3):351-7. doi:10.1001/jama.292.3.351 PMID: 15265850

Related articles on fever

For the fever clinic on Sundays and holidays, see the announcement about the fever clinic on Sundays and holidays; for how to visit, see the page on the fever clinic pre-visit questionnaire and same-day check-in.