About 1 in 10 people with epilepsy have this syndrome. It usually starts between the ages of 12 and 18. It is slightly more common in girls than in boys.
JME Juvenile myoclonic epilepsy is one of the most common epilepsy syndromes that begins in children and young people.
People who develop JME usually do not have any health or developmental problems, although about 1 in 20 have a history of febrile seizures. There is no connection to problems during or before birth. About one-third of children with JME epilepsy may have a family member with epilepsy.
Symptoms of juvenile myoclonic epilepsy
There are 3 different types of seizures that people with JME can get. These are called myoclonic, tonic-clonic, and absence seizures.
All people with JME have myoclonic seizures. Myoclonic seizures cause sudden muscle jerks hands, legs or whole body. The jolts can be strong enough to knock things over – like cups and plates – or cause you to fall.
In a myoclonic seizure, the child:
- has short muscle twitches or jerks in the upper arms, shoulders or neck
- has movements on one or both sides of the body at the same time
- is usually awake and able to think clearly during and immediately after the attack
About 9 out of 10 people with JME also have tonic-clonic seizures. They cause you to freeze (tonic part), pass out, and then immediately have a series of rhythmic jerks (clonic part).
Tonic-clonic seizures often occur after a series or group of myoclonic seizures. If a child gets tonic-clonic seizures, they will usually only have 1 or 2 of them a year. Although sometimes, he may get a cluster of several of these attacks over several weeks.
In this type of attack, the child:
- has convulsions, or stiff muscles and rhythmic body jerks
- turns his eyes back
- it helps
- may pee or poop
- they cannot react during the attack
- is confused and drowsy after the attack
About one-third of people with JME also have absence seizures. This is when the child “switches off” or becomes unresponsive. They are often the first type of seizure in people with JME, sometimes months or years before the onset of myoclonic and tonic-clonic seizures. This seizure begins suddenly in the middle of activity and ends abruptly.
- looks absent or has a staring expression that lasts 5–20 seconds
- may blink or look up
- is not aware of what is happening during the attack
- it returns to normal activity and will not remember having a seizure after it ends
- has lip smacking, chewing movements, or hand fumbling
Seizures in juvenile myoclonic epilepsy usually occur within 30 minutes of waking up in the morning or after a nap. It’s more likely to happen when someone is tired, stressed, or hasn’t had enough sleep.
People with JME are much more likely to have seizures when they don’t get enough sleep. Attacks often occur shortly after waking up or later in the day if you are tired. Eating stress or anxiety can also increase the risk of seizures, especially tonic-clonic seizures.
Over one-third of people with JME are sensitive to light. This means that myoclonic or tonic-clonic seizures are triggered by flashing lights. This is also more likely to happen if the person is tired or has had less sleep.
What causes juvenile myoclonic epilepsy?
The cause of juvenile myoclonic epilepsy is unknown, but it tends to run in families genetics. Genetic changes (mutations) are associated with this condition.
How is juvenile myoclonic epilepsy diagnosed?
If your child has had a seizure, doctor will probably want to see a pediatric neurologist (a doctor who treats problems with the brain, spine, and nervous system). The neurologist will ask questions about what happened during the seizure, perform an examination, and order an EEG to measure brain wave activity.
How is juvenile myoclonic epilepsy treated?
Seizures are usually well controlled with medication, which many children will need to take for life. If not, doctors must try other treatments.
How can parents help?
To help your child live better with epilepsy, be sure to follow the neurologist’s recommendations about:
- taking any medications
- avoiding triggers (such as excessive stress, lack of sleep, flickering lights, certain types of medication)
- taking precautions while swimming or bathing
- consider whether your child should wear a medical ID bracelet
To protect your child during a seizure, make sure other adults and caregivers (family members, teachers, coaches, etc.) know what to do.
Juvenile myoclonic epilepsy is a lifelong condition. But many children go on to live normal lives with a few extra steps taken to keep them safe.
Some children with JME find that their seizures improve as they get older, becoming less intense and occurring less frequently. Some may be able to stop taking it medicines later in life. But most people with JME will need to take epilepsy medication for the rest of their lives. If the drug is stopped, it is common for the attacks to return.