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Valproic acid is the first line drug choice for reducing generalised seizures and myoclonus. Levetiracetam is also effective for both generalised seizures and myoclonus. Clonazepam and high-dose piracetam can alleviate myoclonus. Phenytoin can worsen seizures and may speed up neurodegeneration; carbamazepine, oxcarbazepine, tiagabine, vigabatrin, gabapentin and pregabalin may worsen myoclonus and myoclonic seizures. Other common medications to treat ULD include topiramate and zonisamide. If an individual with Unverricht–Lundborg disease is particularly sensitive to a certain type of stimulus, it is also beneficial to reduce the patient's exposure to that stimulus in order to reduce the likelihood of seizures. Since ULD is progressive and may not get better over time, depression has been documented in many cases, so providing a strong support group of friends, family, and even other individuals with ULD is very beneficial.
While there is no current cure to repair the mutated CSTB gene, several antiepileptic drugs are effective in reducing seizures and helping patients with ULD to manage the symptoms. In addition, new research is being performed to examine the effectiveness of other types of treatments.
In 1999, Sachdeo and colleagues at the University of Medicine and Dentistry of New Jersey and the Robert Wood Johnson Medical School in New Brunswick reported that 33% of the patients in a group of patients taking topiramate experienced a minimum 50% reduction in seizures (specifically drop attacks and tonic–clonics), compared with 8% in the placebo group. It was also found to be effective as an adjunctive therapy in a review published by Drs. Edith Alva Moncayo and Antonio Ruiz Ruiz in March 2003.
Motte reported in 1997 that lamotrigine was effective in the treatment of LGS, with the most common side effect in the treatment group relative to placebo being colds or viral illnesses. Two years later, it was approved by Health Canada for adjunctive therapy in Lennox Gastaut in adults and children. The United States Food and Drug Administration approved it for that in August 1998.
Felbamate is indicated in the use of LGS in the event that everything else fails, and was found to be superior to placebo in controlling treatment resistant partial seizures and atonic seizures. However, it has been known to cause aplastic anemia and liver toxicity.
Antiepileptic drugs (AEDs) are used in most cases to control seizures, however, PCDH19 gene-related epilepsy is generally associated with early-onset development of drug resistant seizures. Existing data supports the use of “rational polypharmacy,” which consists of a step-wise addition of AEDs until a patient responds favorably or experiences intolerable adverse events. In general, as in other types of uncontrolled epilepsy, the use of drugs with different mechanisms of action appears to be more effective than combining drugs with similar mechanisms of action.
No currently marketed AEDs have been extensively studied in PCDH19 gene-related epilepsy and there is no established treatment strategy for girls diagnosed with PCDH19 gene-related epilepsy. Patients may respond well to treatment with levetiracetam and in cases of drug resistance, stiripentol, which is not approved in the U.S. but is available through the FDA Expanded Access IND process.
Life expectancy is only moderately affected by NE because the rate of disease progression is slow. Patients usually survive past 40-50 years of age.
At the hospital, physicians follow standard protocol for managing seizures. Cluster seizures are generally controlled by benzodiazepines such as diazepam, midazolam, lorazepam or clonazepam. The use of oxygen is recommended in the United States, but in Europe it is only recommended in cases of prolonged epileptic status.
Current available treatment is limited to treating the symptoms, not the cause. Seizure frequency can be regulated by the use of drugs such as Clonazepam (or other benzodiazepines) and Sodium Valproate. Clonazepam functions by increasing GABA activity at the GABA receptor. GABA is an inhibitory neurotransmitter and therefore, its increased activity hyperpolarizes cells. Clonazepam has been effective in minimising seizure activity, especially during puberty. Sodium valproate prevents the depolarization of the cell by blocking sodium ion channels and inhibitory GABA enzymes. Both of these anticonvulsants lead to depression of the central nervous system.
The most effective anti-epileptic medication for JME is valproic acid (Depakote). Women are often started on alternative medications due to valproic acid's high incidence of fetal malformations. Lamotrigine, levetiracetam, topiramate, and zonisamide are alternative anti-epileptic medications with less frequent incidence of pregnancy related complications, and they are often used first in females of childbearing age. Carbamazepine may aggravate primary generalized seizure disorders such as JME. Treatment is lifelong. Patients should be warned to avoid sleep deprivation.
Seizures in Dravet syndrome can be difficult to manage but may be reduced by anticonvulsant medications such as clobazam, stiripentol, topiramate and valproate. Because the course of the disorder varies from individual to individual, treatment protocols may vary. A diet high in fats and low in carbohydrates may also be beneficial, known as a ketogenic diet. Although diet adjustment can help, it does not eliminate the symptoms. Until a better form of treatment or cure is discovered, those with this disease will have myoclonic epilepsy for the rest of their lives.
Certain anticonvulsant drugs that are classed as Sodium Channel Blockers are now known to make seizures worse in most Dravet patients. These drugs include carbamazepine, gabapentin, lamotrigine, and phenytoin.
Treatments include cognitive rehabilitation through psychomotor and speech therapy. In addition, valproate is often administered to prevent recurrence of febrile seizures and benzodiazapine is used for long lasting seizures, but these treatments are usually insufficient.
Stiripentol was the only drug for which a double-blind placebo trial was performed and this drug showed efficacy in trials. It acts as a GABAergic agent and as a positive allosteric modulator of GABA receptor. Stiripentol, can improve focal refractory epilepsy, as well as Dravet's syndrome, supplemented with clobazam and valproate was approved in Europe in 2007 as a therapy for Dravet syndrome and has been found to reduce overall seizure rate by 70%. In cases with more drug resistant seizures, topiramate and the ketogenic diet are used as alternative treatments.
Cannabidiol (CBD) has received orphan drug status in the United States, for treatment of Dravet syndrome which will allow it to be studied.
No high quality evidence has shown any drug very useful as of 2013. Rufinamide, lamotrigine, topiramate and felbamate may be useful.
PME accounts for less than 1% of epilepsy cases at specialist centres. The incidence and prevalence of PME is unknown, but there are considerable geography and ethnic variations amongst the specific genetic disorders. One cause, Unverricht Lundborg Disease, has an incidence of at least 1:20,000 in Finland.
Research on myoclonus is supported through the National Institute of Neurological Disorders and Stroke (NINDS). The primary focus of research is on the role of neurotransmitters and receptors involved in the disease. Identifying whether or not abnormalities in these pathways cause myoclonus may help in efforts to develop drug treatments and diagnostic tests. Determining the extent that genetics play in these abnormalities may lead to potential treatments for their reversal, potentially correcting the loss of inhibition while enhancing mechanisms in the body that would compensate for their effects.
Dravet syndrome is a severe form of epilepsy. It is a rare genetic disorder that affects an estimated 1 in every 20,000–40,000 births.
The ketogenic diet mimics some of the effects of starvation, in which the body first uses up glucose and glycogen before burning stored body fat. In the absence of glucose, the body produces ketones, a chemical by-product of fat metabolism that has been known to inhibit seizures.
A modified version of a popular low-carbohydrate, high-fat diet which is less restrictive than the ketogenic diet.
The low glycemic index treatment (LGIT) is a new dietary therapy currently being studied to treat epilepsy. LGIT attempts to reproduce the positive effects of the ketogenic diet. The treatment allows a more generous intake of carbohydrates than the ketogenic diet, but is restricted to foods that have a low glycemic index, meaning foods that have a relatively low impact on blood-glucose levels.
These foods include meats, cheeses, and most vegetables because these foods have a relatively low glycemic index. Foods do not have to be weighed, but instead careful attention must be paid to portion size and balancing the intake of carbohydrates throughout the day with adequate amounts of fats and proteins.
The treatment for seizures may include antiepileptic medications, diet, and vagus nerve stimulator.
The effects of myoclonus in an individual can vary depending on the form and the overall health of the individual. In severe cases, particularly those indicating an underlying disorder in the brain or nerves, movement can be extremely distorted and limit ability to normally function, such as in eating, talking, and walking. In these cases, treatment that is usually effective, such as clonazepam and sodium valproate, may instead cause adverse reaction to the drug, including increased tolerance and a greater need for increase in dosage. However, the prognosis for more simple forms of myoclonus in otherwise healthy individuals may be neutral, as the disease may cause few to no difficulties. Other times the disease starts simply, in one region of the body, and then spreads.
The journal of child neurology published a paper in 2012, Buccal swab analysis of mitochondrial enzyme deficiency and DNA defects in a child with suspected myoclonic epilepsy and ragged red fibers (MERRF), discusses possible new methods to test for MERRF and other mitochondrial diseases, through a simple swabbing technique. This is a less invasive techniques which allows for an analysis of buccal mitochondrial DNA, and showed significant amounts of the common 5 kb and 7.4 kb mitochondrial DNA deletions, also detectable in blood. This study suggests that a buccal swab approach can be used to informatively examine mitochondrial dysfunction in children with seizures and may be applicable to screening mitochondrial disease with other clinical presentations.
Proceedings of the National Academy of Science of the United States of America published an article in 2007 which investigate the human mitochondrial tRNA (hmt-tRNA) mutations which are associated with mitochondrial myopathies. Since the current understanding of the precise molecular mechanisms of these mutations is limited, there is no efficient method to treat their associated mitochondrial diseases. All pathogenic mutants displayed pleiotropic phenotypes, with the exception of the G34A anticodon mutation, which solely affected aminoacylation.
The mainstay treatment of epilepsy is anticonvulsant medications, possibly for the person's entire life. The choice of anticonvulsant is based on seizure type, epilepsy syndrome, other medications used, other health problems, and the person's age and lifestyle. A single medication is recommended initially; if this is not effective, switching to a single other medication is recommended. Two medications at once is recommended only if a single medication does not work. In about half, the first agent is effective; a second single agent helps in about 13% and a third or two agents at the same time may help an additional 4%. About 30% of people continue to have seizures despite anticonvulsant treatment.
There are a number of medications available including phenytoin, carbamazepine and valproate. Low-quality evidence suggests that phenytoin, carbamazepine, and valproate may be equally effective in both focal and generalized seizures. Controlled release carbamazepine appears to work as well as immediate release carbamazepine, and may have fewer side effects. In the United Kingdom, carbamazepine or lamotrigine are recommended as first-line treatment for focal seizures, with levetiracetam and valproate as second-line due to issues of cost and side effects. Valproate is recommended first-line for generalized seizures with lamotrigine being second-line. In those with absence seizures, ethosuximide or valproate are recommended; valproate is particularly effective in myoclonic seizures and tonic or atonic seizures. If seizures are well-controlled on a particular treatment, it is not usually necessary to routinely check the medication levels in the blood.
The least expensive anticonvulsant is phenobarbital at around $5 USD a year. The World Health Organization gives it a first-line recommendation in the developing world and it is commonly used there. Access however may be difficult as some countries label it as a controlled drug.
Adverse effects from medications are reported in 10 to 90% of people, depending on how and from whom the data is collected. Most adverse effects are dose-related and mild. Some examples include mood changes, sleepiness, or an unsteadiness in gait. Certain medications have side effects that are not related to dose such as rashes, liver toxicity, or suppression of the bone marrow. Up to a quarter of people stop treatment due to adverse effects. Some medications are associated with birth defects when used in pregnancy. Many of the common used medications, such as valproate, phenytoin, carbamazepine, phenobarbitol, and gabapentin have been reported to cause increased risk of birth defects, especially when used during the first trimester. Despite this, treatment is often continued once effective, because the risk of untreated epilepsy is believed to be greater than the risk of the medications. Among the antiepileptic medications, levetiracetam and lamotrigine seem to carry the lowest risk of causing birth defects.
Slowly stopping medications may be reasonable in some people who do not have a seizure for two to four years; however, around a third of people have a recurrence, most often during the first six months. Stopping is possible in about 70% of children and 60% of adults.
Jeavons syndrome is a lifelong disorder, even if seizures are well controlled with antiepileptic drugs. Men have a better prognosis than women. There is a tendency for photosensitivity to disappear in middle age, but eyelid myoclonia persists. It is highly resistant to treatment and occurs many times a day, often without apparent absences and even without demonstrable photosensitivity.
Like many mitochondrial diseases, there is no cure for MERRF, no matter the means for diagnosis of the disease. The treatment is primarily symptomatic. High doses of Coenzyme Q10, B complex vitamins and L-Carnitine are the drugs that patients are treated with in order to account for the altered metabolic processed resulting in the disease. There is very little success with these treatments as therapies in hopes of improving mitochondrial function. The treatment only alleviates symptoms and these do not prevent the disease from progressing. Patients with concomitant disease, such as diabetes, deafness or cardiac disease, are treated in combination to manage symptoms.
A ketogenic diet (high-fat, low-carbohydrate, adequate-protein) appears to decrease the number of seizures and eliminate seizures in some, however further research is necessary. It is a reasonable option in those who have epilepsy that is not improved with medications and for whom surgery is not an option. About 10% stay on the diet for a few years due to issues of effectiveness and tolerability. Side effects include stomach and intestinal problems in 30%, and there are long-term concerns about heart disease. Less radical diets are easier to tolerate and may be effective. It is unclear why this diet works. Exercise has been proposed as possibly useful for preventing seizures with some data to support this claim.
In people with coeliac disease or non-celiac gluten sensitivity and occipital calcifications, a gluten-free diet may decrease the frequency of seizures.
Seizures in cats are caused by various onsets. Cats can have reactive, primary (idiopathic) or secondary seizures. Idiopathic seizures are not as common in cats as in dogs however a recent study conducted showed that of 91 feline seizures, 25% were suspected to have idiopathic epilepsy. In the same group of 91 cats, 50% were secondary seizures and 20% reactive.
Based on anecdotal evidence, the drugs of choice are those used for other idiopathic generalized epilepsies. Valproate alone, or most probably in combination with clonazepam, levetiracetam, lamotrigine or ethosuximide, appears to be the most effective regimen. The choice of the second drug depends on the main seizure type. Clonazepam is highly efficacious in eyelid myoclonia and myoclonic jerks. Of the newer antiepileptic drugs, levetiracetam may be the most effective, because of its anti myoclonic and anti photosensitive properties. Lamotrigine is very effective in absence seizures but may exaggerate myoclonic jerks.
Contra-indicated drugs are: Carbamazepine, gabapentin, oxcarbazepine, phenytoin, pregabalin, tiagabine and vigabatrin.
Lifestyle and avoidance of seizure precipitants are important. Non-pharmacological treatments used for photosensitive patients (such as wearing special glasses or the newly commercially available blue Z1 lenses) should be employed in Jeavons syndrome when photosensitivity persists.
Seven anti-epileptic drugs are approved for use in cases of suspected primary generalized epilepsy:
- Felbamate
- Levetiracetam
- Zonisamide
- Topiramate
- Valproate
- Lamotrigine
- Perampanel
Valproate, a relatively old drug, is often considered the first-line treatment. It is highly effective, but its association with fetal malformations when taken in pregnancy limits its use in young women.
All anti-epileptic drugs (including the above) can be used in cases of partial seizures.
The lack of generally recognized clinical recommendations available are a reflection of the dearth of data on the effectiveness of any particular clinical strategy, but on the basis of present evidence, the following may be relevant:
- Epileptic seizure control with the appropriate use of medication and lifestyle counseling is the focus of prevention.
- Reduction of stress, participation in physical exercises, and night supervision might minimize the risk of SUDEP.
- Knowledge of how to perform the appropriate first-aid responses to seizure by persons who live with epileptic people may prevent death.
- People associated with arrhythmias during seizures should be submitted to extensive cardiac investigation with a view to determining the indication for on-demand cardiac pacing.
- Successful epilepsy surgery may reduce the risk of SUDEP, but this depends on the outcome in terms of seizure control.
- The use of anti suffocation pillows have been advocated by some practitioners to improve respiration while sleeping, but their effectiveness remain unproven because experimental studies are lacking.
- Providing information to individuals and relatives about SUDEP is beneficial.