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Fever Cramps

By Bjarne Lühr Hansen PhD, MD and Philipp Skafte-Holm MD, Mentor Institute

Fever cramps is a shocking experience to most parents. A child with fever cramps is unconscious. At first, the child’s body gets stiff and later on fast twitches in arms and legs appear. The fever cramp does not harm the child. Children grow out of the disease and manages just well as all other children later on in life. You must treat fever cramp with a special kind of medication. You must call the doctor at once if the child has fever cramps.

Fever cramps is a shocking experience to most parents who think that their child is dying, strangulated or having a heart attack. There is no reason to be afraid. Scientific studies has shown that fever cramps usually are benign. We do not know why some children has fever cramps and others not. However, we know that children with fever cramp does not have epilepsy or other diseases in the brain.

Fever cramps occur with 2 – 5 % of all children. Especially, children between 6 months and 5 years have fever cramps. Fever cramps is – as the word says – cramps that occur with a feverish child. To talk about fever cramps the child’s temperature must be over 38.0oC. Normally the child has an infection that causes fever (e.g. common cold, middle ear infection or throat infection) and then the cramps come like a bolt from the blue.

Most fever cramps starts, when you are unable to contact the child. At the same time, the child becomes stiff in the whole body – arms and legs stretched. After a few seconds, the arms and legs are bended and stretched in very fast twitches. A typical fever cramp attack lasts less than 5 minutes. Hereafter, the child awakens and will – except from the fever – act as usual. This kind of fever cramps do not harm the child. In rare cases, the fever cramp develops in another way – the doctors then talk about complicated fever cramps. Complicated fever cramps can hurt the child and therefore the parents should contact a doctor immediately.

Four signs of complicated and dangerous fever cramps:

  1. Fever cramps only occur in one half of the body. That means that the very fast twitches in arms and legs only occur on the right or left side – not on both sides as normal.
  2. The cramp lasts for more than 30 minutes.
  3. The fever cramps occur two times after each other within 24 hours.
  4. After the child has awakened there are paralyses of e.g. one of the legs or one of the arms (the child cannot use the arm or leg).

The fever cramps are not dangerous for the child but in rare cases – where there is complicated fever cramps – it can harm the child.

Every third child who has had a seizure of fever cramps will later on in life have a new seizure when the child has a fever. It is unknown why some children have one seizure and others have several seizures. However, it is known that if the first seizure appears before the child is 15 months old and neither parents nor siblings have had fever cramps, there is a higher risk of having more than one seizure.

In other words, if the child is more than 15 months old at the first seizure and neither parents nor siblings have had fever cramps - then most children (9 out of 10) will only have a single seizure of fever cramp. If the child is younger than 15 months at the first fever cramp and there is fever cramps in the family – more than half of the children will have a new seizure of fever cramps.

Children with fever cramps outgrow the disease. Most children does not have epilepsy later in life. Fever cramps do not affect the child’s intelligence or school performance. So even though fever cramps appear serious, in the end, the child is not harmed.

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By giving the child a special kind of medicine, you can stop the fever cramps (diazepam). The medicine works within few minutes. You can only buy the medicine on prescription. The same medicine is used prophylactic, meaning that the parents give the child medication if the temperature rises above 38.0oC. The medicine is only used prophylactic, if the child is in the high-risk group (cf. above). Therefore, antipyretics cannot be recommended to children who have had fever cramps before.

What can you do?

A child with fever must have fluid, be lightly dressed and stay in a cool room.

Contact the doctor tomorrow

If the child still has a fever.

Contact the doctor immediately

If the child has fever cramps.