Absence Seizure Medications: What You Need To Know

Absence epilepsy is a condition characterized by recurrent seizures. Childhood absence epilepsy affects around six to eight in every 100,000 children¹ annually and accounts for up to 17% of epilepsy cases in school-aged children. Absence epilepsy generally appears between the ages of four and 12.

However, in rare cases, the condition develops in adulthood. For the most part, once children with absence seizures reach adulthood, their seizures spontaneously resolve. 

During an absence seizure, your child will look like they’re staring off blankly into space for a few seconds. They will stop what they’re doing for a few seconds, then carry on as though nothing happened once the seizure has stopped. After the episode, a person with an absence seizure will have no memory of the event.

While they typically last a few seconds, absence seizures can last as long as a few minutes; however, it’s very rare. Seizures can occur as often as ten to 30 times daily.

Researchers don’t know what causes absence seizures. However, the condition is linked to abnormal electrical activity in the brain, and treatments aim to stabilize electrical activity to prevent seizures from occurring. Children who take medications for absence seizures no longer need to take medications when they’ve outgrown their condition.

Which medications treat absence seizures? 

Ethosuximide 

An anticonvulsant, ethosuximide is generally the first choice for absence seizures. It’s effective in around half of all cases of childhood and adolescent absence epilepsy. However, like all medications, ethosuximide carries a risk of undesirable side effects, including headaches, dizziness, fatigue, stomach cramps, nausea, and vomiting. 

Ethosuximide moderates specific calcium channels, influencing the frequency at which certain neurons send signals and thus stabilizing electrical activity in the brain. 

Valproic acid 

Valproic acid is an effective and fast-acting treatment option for absence seizures. In their analysis of relevant literature,² one team of researchers found that 63.1% of children taking valproic acid were seizure-free after just three months. At the one-year mark, the success rate was even higher, at 68.4%.

Possible side effects include mood swings, back pain, diarrhea, dizziness, drowsiness, headaches, and changes in appetite. 

Valproic acid is thought to work by increasing the amount of gamma-aminobutyric acid (GABA), the principal inhibitory chemical messenger in the brain. 

Lamotrigine

Lamotrigine is an antiepileptic drug more commonly used as a first-line treatment for other types of seizures, including primary generalized tonic-clonic seizures. While it may be well-suited for some people with the condition, lamotrigine has been found to be less successful than ethosuximide and valproic acid in treating absence seizures.

Common side effects of lamotrigine include drowsiness, dizziness, tremors, blurred vision, nausea, vomiting, and loss of balance. 

Lamotrigine’s mechanism of action is poorly understood, but research indicates it helps stabilize the brain’s electrical activity by selectively acting on sodium channels and thus inhibiting excitatory neurotransmitters in the brain. 

Topiramate

Topiramate is typically prescribed for other types of epilepsy, and while it’s not commonly used to treat absence seizures, some preliminary evidence³ has found that topiramate could be effective. Further studies are required to determine whether topiramate is as effective as other absence epilepsy medications.

Side effects of topiramate may include nervousness, weakness, drowsiness, tremors, headaches, and nose bleeds.

Zonisamide 

Research⁴ shows zonisamide has a low incidence of side effects and may help treat typical absence seizures. It is commonly used in conjunction with other medicines for treating different forms of epilepsy. More research is needed to determine the efficacy of zonisamide compared with conventional treatment options. 

Gabapentin, oxcarbazepine, carbamazepine, phenytoin, phenobarbital, tiagabine, and vigabatrin are anti-seizure medications that have all been found to be ineffective in treating absence seizures, many of which even worsen absence epilepsy and are to be avoided. 

Early diagnosis and treatment will help you effectively manage your condition. Sticking to a treatment protocol can help you eliminate your seizures and minimize the side effects of your medication. 

Prompt treatment is particularly important in the most commonly affected population — children — as every seizure can interrupt their learning process. 

What if the medication doesn’t work?

In around 30%⁵ of children with absence epilepsy, the condition is resistant to medication. In those cases, doctors may recommend alternative treatment protocols to reduce the impact of their condition. 

Surgery

Surgery is one potential treatment avenue for people who are not responding to medication. The most common surgery is a temporal lobectomy. During this procedure, a specialized doctor removes the part of the brain where most seizures start. 

Most patients outgrow absence seizures, and surgery is generally not required or recommended, as it carries risks of psychiatric disturbances, cognitive disorders, and visual field defects. 

Deep brain stimulation

Deep brain stimulation (DBS) has been receiving more attention in recent years for the treatment or alleviation of symptoms associated with a variety of conditions. DBS operates by sending electrical signals to electrodes implanted in the brain. Research⁶ indicates this treatment is effective in treating absence seizures. 

Deep brain stimulation requires a surgical procedure to implant the electrodes into the brain. Most doctors and patients prefer to try less invasive options first. 

Ketogenic diet

A ketogenic diet has been successfully used for treatment-resistant cases of absence epilepsy in children. However, further research is needed to understand how this diet may help and how effective it is. The keto diet increases the amount of GABA, an inhibitory messenger in the brain, which may help stabilize the hyperactivity in the brain that triggers seizures. 

Like many conditions, there’s evidence epilepsy may be affected by sleep. Sleep deprivation has been shown to increase seizure frequency and duration. A healthy sleep routine may improve symptoms and boost overall wellness when used alongside the appropriate medications. 

When to see a doctor

If your child isn’t diagnosed but exhibits signs of absence seizures, including the characteristic blank stare and others, like intense, prolonged stillness without explanation or fluttering eyelids, and a lack of awareness of the episode, see a doctor for a diagnosis. 

Most people with epilepsy can lead happy, fulfilling lives. However, it’s essential to consult a doctor who can help rule out more severe causes and recommend treatments to improve your child’s condition. 

The lowdown

Absence seizures, often arising in childhood and resolving by adulthood, are characterized by vacant seizure episodes. Doctors treat absence seizures with antiepileptic medications, but rarely, medications are ineffective, and more invasive interventions are needed. 

Early intervention and treatment are essential to ensure the condition doesn’t drastically affect the child’s life and schooling, so speak with a doctor if you suspect your child has absence epilepsy. 

The good news is that, generally, absence epilepsy has a favorable outlook and doesn’t require treatment beyond the teenage years.