Febrile Convulsions in Young Children: What They Are and What to Do

Watching a child have a febrile convulsion is one of the most frightening things a parent will experience. The child suddenly goes stiff, their eyes roll back, their face changes colour, and they begin to jerk rhythmically. They don't respond to their name, can't be roused, and may produce strange breathing sounds or stop breathing momentarily. For the parent watching, the brain reaches the conclusion that the child is dying, often within seconds. The seizure usually lasts less than five minutes; the parental memory of those minutes is sometimes a permanent feature of family life.

The genuinely reassuring fact about simple febrile convulsions — the kind that affects around 1 in 30 children at some point between six months and five years — is that, despite how they look, they very rarely cause harm. Children who have one usually grow out of them, don't develop epilepsy, don't have brain damage, and are completely fine afterwards. The work for parents is mostly in surviving the moment of the seizure (knowing what to do), and then in not letting the trauma of the experience overshadow the calm reality of the child's actual prognosis.

This article covers what to do in the moment, what counts as serious enough to call 999, what to expect afterwards, and how to prepare for the possibility of recurrence — which happens in about a third of cases. Healthbooq supports parents through acute medical events in young children.

What a Febrile Convulsion Looks Like

A typical simple febrile convulsion:

• Sudden onset, often without warning. The child may have just been feeling slightly off, or may have suddenly become hot.
• Loss of consciousness. The child becomes unresponsive — won't answer, won't track with their eyes, doesn't react to their name.
• Body changes. The child usually goes stiff (tonic phase) for several seconds, then begins rhythmic jerking of arms and legs (clonic phase). The eyes may roll up or to one side. The face may change colour — pale, sometimes blue around the lips. Some children produce frothy saliva or vomit briefly.
• Breathing changes. Breathing may become irregular, noisy, or briefly stop. They may make groaning or grunting sounds.
• Loss of bladder or bowel control may occur.
• Duration: usually under 2–3 minutes, almost always under 5. Some last seconds.
• Recovery. The child gradually becomes responsive but is often drowsy, confused, and exhausted afterwards (the "postictal" phase). They may want to sleep deeply for an hour or two.

The "looks like dying" perception is universal among parents who have witnessed one. It does not match the actual risk. Almost all simple febrile convulsions resolve fully without harm.

Why It Happens

Children between 6 months and 5 years are in a developmental window where their brains are more susceptible to seizure activity in the context of fever. The mechanism isn't fully understood, but the rate of change of body temperature seems to matter more than the absolute temperature reached — the convulsion may be the first sign that a child is becoming febrile, not a sign of a particularly extreme fever. Many children have their convulsion at the start of a fairly modest viral illness.

Genetic predisposition is real. About a quarter of children who have a febrile convulsion have a family member who also had one. If your child has had one, knowing whether you, your siblings, or grandparents had febrile convulsions as children is useful information.

The brain matures past this vulnerability by about age 5–6. After that age, the susceptibility to fever-triggered seizures essentially disappears.

Simple vs Complex Febrile Convulsions

This distinction matters for what investigation and follow-up the child needs:

• Lasts less than 15 minutes (most under 5)
• Generalised — affects whole body equally
• Does not recur within 24 hours / the same illness episode
• Most common type (around 70–75% of febrile convulsions)
• Excellent prognosis

• Lasts more than 15 minutes, OR
• Focal — affects only one side of the body, or only specific muscle groups, OR
• Recurs within 24 hours / during the same illness episode
• Around 25–30% of febrile convulsions
• Warrants more thorough assessment, sometimes including EEG and brain imaging
• Slightly higher (but still small) risk of later epilepsy

Most parents won't be able to make this distinction definitively in the moment — that's not the parent's job. The clinical team after the event will determine which type. What you need to do in the moment is the same in both cases.

What To Do, In Order

When you realise it's happening:

1. Note the time. Look at the clock or start the timer on your phone. The duration of the seizure is the most important piece of clinical information you can provide afterwards. Without it, you will dramatically overestimate — what felt like 15 minutes was usually under 3.

1. Lay the child somewhere safe. A bed, the sofa, the floor with a soft towel under the head. The aim is preventing injury during the jerking phase, particularly to the head. If they're already on the floor, that's fine.

1. Roll them onto their side. This is the recovery position — head turned to the side, body slightly rolled. It allows saliva, vomit, or fluid to drain rather than going down the airway. If they're rigid and you can't easily roll them, that's okay; do it once the stiffness eases.

1. Move objects out of the way. Anything sharp or hard near them.

1. Loosen tight clothing. Particularly around the neck.

1. Do not restrain them. Don't try to hold their limbs still. The jerking is not voluntary; restraining doesn't stop it and can cause injury.

1. Do not put anything in their mouth. Not your fingers, not a spoon, nothing. The myth that a person having a seizure can swallow their tongue is wrong — the tongue cannot be swallowed. Putting things in the mouth risks injury to the child and to your fingers, and obstructs the airway.

1. Note what you can. Which side of the body is affected? Eyes rolling left or right? Twitching of the whole body or just part? You don't need to keep notes — just observe so you can tell the doctor afterwards.

1. Stay with them. Talk calmly, even though they can't respond. Other adults present can call for help.

When To Call 999

Call 999 immediately if:

• The seizure has been going on for 5 minutes or more. A seizure lasting more than 5 minutes is unlikely to stop on its own and may need emergency medication.
• This is the child's first ever seizure — call 999 to get them assessed even if it's brief.
• You're not sure whether this is a febrile convulsion or another kind of seizure (especially if there's no fever).
• The child is having difficulty breathing during or after the seizure (beyond brief breathing changes during the seizure itself).
• The child has injured themselves during the seizure.
• The child has another seizure shortly after the first one stops.
• The child does not become responsive within 10 minutes of the seizure ending.
• You're worried — your concern alone is enough reason to call. Triage will help.

For a child who has had previous febrile convulsions and this one resolves in under 5 minutes:

• You don't necessarily need an ambulance, but you should still get them assessed today — call NHS 111 or your GP for guidance.

After the Seizure

The post-ictal phase is normal and looks alarming in its own right:

• Deep drowsiness; the child may sleep for 30 minutes to a couple of hours.
• Confusion when they wake — may not know where they are, may seem very young suddenly.
• Crying or distress as awareness returns.
• Mild floppiness or weakness for a while.
• They may be ravenously thirsty or hungry afterwards.

What to do:

• Keep them on their side, comfortable.
• Don't try to give them food, drink, or medication while they're not fully responsive — choking risk.
• Once they're awake and swallowing normally, offer fluids.
• Comfort them — they may be confused and frightened, with no memory of the seizure itself.
• Get them seen by a doctor that day, even if they seem fully recovered.

Why a Doctor Sees Them

After a first febrile convulsion, the child should be seen by a doctor — typically in A&E if the seizure has just happened, or by their GP if some hours have passed and they've fully recovered. The reasons:

• Confirm the diagnosis. Most are clearly febrile convulsions, but the doctor will want to rule out other causes (meningitis, epilepsy, hypoglycaemia, electrolyte disturbance).
• Find the source of the fever. What's causing the underlying illness? Usually a virus; sometimes a UTI or other treatable infection.
• Assess for complex features. If the seizure was prolonged, focal, or recurred — further investigation may be needed.
• Provide guidance for future events. Most parents leave with a written plan: what to do if it happens again, when to call 999, follow-up if needed.

For a child with previous simple febrile convulsions and a brief, classic recurrence, an in-person same-day assessment is still recommended, but it may be by a GP rather than an emergency department.

After the First One: What to Expect

Many parents come away from a first febrile convulsion convinced their child has epilepsy or has suffered brain damage. The actual data:

• Brain damage from a simple febrile convulsion: essentially never. Imaging studies of children after febrile convulsions show no structural changes. Long-term follow-up shows no increase in cognitive, behavioural, or developmental problems.
• Epilepsy risk after a simple febrile convulsion: about 2–3%, compared with about 1% in the general population. A small absolute increase. Most children with one or more simple febrile convulsions never have a non-fever-related seizure.
• Recurrence: about 1 in 3 children will have another febrile convulsion with a future fever. Higher recurrence risk if: under 18 months at first event, family history, lower temperature at which the seizure occurred. Most who recur do so within a year.
• Outgrowing it: by age 5–6, the brain is no longer susceptible to fever-triggered seizures.

Can You Prevent Future Ones?

Probably not, in any reliable way. The major studies are clear: routine paracetamol or ibuprofen at the first sign of fever does not significantly reduce the risk of febrile convulsion in children prone to them. The convulsion is triggered by the rate of temperature rise, not the height; by the time you've noticed the fever, the brain has already had its trigger.

What this means practically:

• Treat fever for the child's comfort, not to prevent convulsions. Antipyretics work for what they're for; they don't reliably prevent seizures.
• Don't go into a panic of constant temperature-checking and dosing. It doesn't help and creates a stressful family atmosphere around minor illnesses.
• Some children with frequent or prolonged febrile convulsions are prescribed a buccal or rectal medication (buccal midazolam or rectal diazepam) for emergency use if a seizure goes on for more than 5 minutes. This is decided with a paediatrician.

Living With the Possibility of Recurrence

After a first febrile convulsion, many parents are anxious about every fever. Some practical steps:

• Know the plan. What you do if it happens again. Write it down. Share it with anyone who looks after your child (other parent, grandparents, nursery, childminder).
• Inform the nursery or childminder. They should know your child has had a febrile convulsion and what to do if one happens. Most have policies in place.
• Have a working thermometer at home, but don't measure obsessively. Treat fever in the same way you would if your child had no convulsion history — for comfort, with normal monitoring.
• Know what does and doesn't warrant 999 (see the list above). Routine fevers do not. A seizure lasting over 5 minutes does.
• Talk to your child about it, age-appropriately. Older toddlers may have some memory of feeling strange or being told they had one. A simple, calm explanation is better than mystery.

A Note on Trauma for Parents

Watching a febrile convulsion is genuinely traumatic for many parents. Some develop persistent anxiety, intrusive memories, or excessive vigilance about every fever afterwards. This is a real psychological response, not weakness.

If you're finding that:

• You're checking your child obsessively while they sleep months after the event.
• You can't shake the image of the seizure from your head.
• You feel anxious to the point of dysfunction whenever your child has a slight illness.
• You're avoiding situations (nursery, going out, leaving the child with anyone else).

…that's worth taking to a GP. Brief CBT for traumatic memory associated with the event is effective and often only needs a few sessions.

The Bigger Picture

The reassurance you most need after a first febrile convulsion is the most important sentence in this article: a simple febrile convulsion, terrifying as it looks, does not damage your child's brain, does not significantly increase their risk of epilepsy, and is something most children grow out of completely by age 5 or 6.

What you need to know in the moment — lie them on their side, time it, don't restrain, don't put anything in the mouth, call 999 if it goes past 5 minutes — fits in a sentence and is the actual practical work. The rest is being kind to yourself through what was a horrifying experience and trusting the very strong evidence that your child is going to be fine.

Febrile convulsions — seizures triggered by fever in children aged six months to five years — are common, affecting approximately one in thirty children. They are terrifying to witness but, in their simple form, are almost always brief (under five minutes), self-limiting, and not associated with brain damage or epilepsy. A child who has a febrile convulsion should be assessed by a doctor after the event, but the seizure itself is managed by keeping the child safe, timing the seizure, and calling 999 if it lasts more than five minutes.