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The neurological care of DDS individuals with epilepsy should strive to optimize quality of life by minimizing the impact of seizures on the cognitive and functional abilities on the individual. The care of a new individual with a prior diagnosis of epilepsy or an established client who develops seizures should begin with a neurological evaluation. The goals of this evaluation should be

The basic elements of the epilepsy care plan should include

Participants in this process should include the client, the individual's family, the interdisciplinary care team, the primary care physician, and a consulting neurologist.

Not all transient spells of altered behavior or awareness are seizures, and isolated seizures do not necessarily imply a diagnosis of epilepsy. When dealing with a new individual with established spells or an established individual with new spells, the first step is to assure the accuracy of the diagnosis. To make an accurate diagnosis the physician must have a complete description of what occurs during a spell.

Seizures can occur in response to provocative factors attending acute physiological stress and may not represent a continuing disorder of brain function that would require further treatment. Non-epileptic spells can follow fainting, or be caused by trauma, metabolic disturbance, or medicines. Behavioral episodes can occur that mimic epileptic seizures.

Because individuals may be unconscious or unaware of their spells, it is important that a clear description of witnessed events be communicated to the evaluating physician. Caregivers who witness new spells should write down their observations using simple common words, avoiding medical jargon that could be misinterpreted. Video-taped documentation of unusual behaviors or spells is invaluable, although appropriate permission should be obtained before recordings are made.

During the initial neurological evaluation, or if the individual's care is being transferred to a new neurologist, all effort should be made to provide documented historical information relevant to the understanding of the epilepsy. This would include:

1. what is known of the individual's gestation, labor and delivery,
2. the presence of post-natal injury or infection,
3. subsequent illness during infancy or adolescence, and/or
4. a family history of epilepsy.

There should also be documentation of the circumstances surrounding the onset of the epilepsy, including

• a description of initial seizures and
• the results of any early diagnostic testing, such as lumbar puncture (spinal tap), electroencephalography (EEG), or brain imaging (CT scan or MRI).

In cases of established epilepsy, it is helpful to provide a synopsis of the course of the disorder, including seizure frequency, changes in seizure type, and the beneficial or toxic effects of specific anticonvulsant medicines.

In the course of an evaluation, additional testing may be indicated to confirm the diagnosis and to determine a cause. Epileptic seizures can be differentiated from non-epileptic spells such as fainting or behavioral episodes using 24-hour ambulatory EEG monitoring or continuous (inpatient) EEG/Video monitoring to record brain electrical activity during a habitual spell.

Epilepsy is the symptomatic expression of brain dysfunction, and the rational therapy of epilepsy should be directed by knowledge of the underlying cause of that dysfunction. However, the cause of brain dysfunction in the majority of people with individual disability is seldom completely understood. Nevertheless, an attempt should be made to determine the cause of the epilepsy, if only to improve communication between health care providers. In some cases, the resulting information can influence or improve the treatment of the disorder.

Although the history is the most important element of the diagnostic process, the results of prior laboratory tests are also helpful. These can include:

1. blood chemistry measurements,
2. cerebrospinal fluid analysis (lumbar puncture),
3. electroencephalography (EEG),
4. brain imaging (CT scan or MRI), and/or
5. continuous EEG/Video monitoring.

The basic elements of the epilepsy care plan are as follows:

• the definition of seizure type(s),
• the development of a seizure response protocol, and
• the formulation of an anticonvulsant treatment program.

Different people may have seizures with markedly different clinical manifestations, and individuals may have multiple seizure types. Once the diagnosis of epilepsy is verified, management depends on the accurate recognition of individual seizures to allow immediate response and to assess control by establishing the event frequency. Although physicians characterize seizures with an international classification scheme, schemes are subject to revision, and poorly defined jargon can interfere with care. The care team should participate in defining a person's seizures and agreeing on common terms for their description.

Observations made during witnessed seizures should be discussed and condensed into a seizure description that is individualized for each person. This description should use common words rather than medical jargon. A shortened name can also be developed that may include elements of the international classification of seizures (Appendix I.). The condensed description should include generally agreed upon upper limits for quantitative aspects of the should include generally agreed upon upper limits for quantitative aspects of the event, such as maximum duration or usual cluster frequency, so that variations can be recognized, recorded, and acted on. After the condensed description and seizure name are approve by a physician, they should be incorporated into a seizure record.

A seizure occurrence should trigger a pre-established response. The response protocol should be developed by the care team with the goals of reducing the likelihood of injury during a seizure and the assessment of the effects of a seizure when it ends. The response should be individualized and can be expected to vary widely between individuals. It is possible that some seizures will require as little response as documenting the occurrence , while other seizures will prompt immediate medical evaluation.

In people with intellectual disability, the primary seizure-related risks are physical injury and aspiration pneumonia. Most seizures are self-limited by their nature, and the immediate care of the person during seizure should be directed toward preventing injury or aspiration.

A. Risks Associated with Specific Seizures Types

B. Response for seizures of longer duration and/or increased clusters

C. Documentation

Antiepileptic medicines reduce seizure frequency and can eliminate seizures in 40 to 80% of patients. However, people with intellectual disability are the least likely to have complete seizure control and are the most likely to require the use of multiple antiepileptic medicines at higher doses. Sedation and other adverse effects will be more common and more disabling.

 Treatment decisions should consider the positive and negative effects of antiepileptic drug use. The desire for complete seizure control should be balanced with optimization of overall function.

Therapy with a single antiepileptic drug (monotherapy) is preferred over multiple antiepileptic drugs (polytherapy) if at all possible. The dose of the single antiepileptic drug should be increased until it is effective or until side-effects appear. If ineffective, monotherapy with an alternative antiepileptic drug should be considered before polytherapy is used. While the addition of a second antiepileptic drug can improve seizure control in 10% of patients, it will cause adverse effects in 90%. When possible, the choice of antiepileptic drug should be directed by the specific epilepsy syndrome. It is recognized that in people with mental retardation, secondary generalized epilepsy may predominate and the no specific antiepileptic drug may offer a clear advantage. However, it is clear that barbiturates (phenobarbital, primidone, mephobarbital) are more sedating.

Factors to be considered when choosing or using an antiepileptic drug include the pharmacokinetics of absorption, distribution, and elimination. For example, the oral suspension form of phenytoin (Dilantin) has low solubility and incomplete but rapid absorption. Absorption is further reduced by feeding solutions. If delivered by gastric tube, continuous feedings should be suspended before and after each dose, and doses should be given twice a day. On the other hand, sustained-release phenytoin (Dilantin Kapseals) has slow absorption and a half-life of more than 24 hours, making once-a-day dosing an advantage for people in supported living, where compliance or the effect of missed doses may be an issue.

Carbamazepine, phenytoin, phenobarbital, and primidone increase the activity of liver enzymes (induction) and result in decreased serum levels of antiepileptic drugs and other medications that are metabolized by the liver. This can reduce the effectiveness of medicines such as theophylline, oral contraceptives, warfarin, and haloperidal. Some medications inhibit the metabolism of anticonvulsants producing increased levels and toxic symptoms. Erythromycin, isoniazid, propoxyphene, diltiazem, verapamil, and cimetidine can increase carbamazepine levels. Chloramphenicol, sulfonamides, isoniazid, disulfiram, and cimetidine can increase phenytoin levels. Methylphenidate, propoxyphene and valproic acid can increase phenobarbital level. Cimetidine, erythromycin, and phenothiazines can increase valproate levels. (See Table, Appendix IV.)

Antiepileptic medication interactions are common and the actual effect of combining medications will be difficult to predict. In general, if there is a clear need for the use of a new medication, it should be used according to its' indications. Antiepileptic drug levels can subsequently be measured to test for major changes in pharmacokinetics caused by drug interaction. However, when suitable equivalent alternatives are available they should be used, as would be the case for erythromycin, propoxyphene (Darvon) or cimetidine (Tagamet).

Antiepileptic drug blood levels are obtained to determine if the oral dose is adequate or to explain the cause of toxic symptoms, especially if polytherapy if used. When possible, blood should be sampled just prior to administration of the morning dose.

Serum levels commonly are obtained

• after new anticonvulsants are instituted,
• if there is an unexpected change in seizure frequency, or
• when signs or symptoms of toxicity appear.

The same indications would hold for blood work designed to screen for metabolic or hematological changes that accompany antiepileptic drug use.

Routine blood testing at intervals less than one year should be avoided, unless it is known that a client has a specific sensitivity to a given agent. For example, hyponatremia is not uncommon with the use of carbamazepine, and more frequent monitoring could be justified by a past history of marked variation in serum sodium levels. In contrast, antiepileptic medicines commonly increase plasma gamma glutamyl transferase (GGT) and repeated measurements are seldom helpful. In healthy individuals, the cost-effectiveness of any routine blood chemistry measurement is seriously questioned. This opinion must be tempered by the presence of higher co-morbidity in people with mental retardation who have epilepsy.

Individuals with intellectual disability who have complete control of their epilepsy with a single antiepileptic drug should be evaluated by a neurologist once every two years.

Individuals on polytherapy or those with incomplete seizure control should be seen at least once a year, or more frequently as specified by the neurologist.

Antiepileptic medications can be withdrawn when there are

• two years of complete seizure control,
• a normal neurological examination,
• a normal electroencephalogram (EEG), and
• normal brain imaging studies (CT or MRI).

By definition, people with intellectual disability do not meet these criteria. However, antiepileptic drug withdrawal can be considered if seizures have been a single type and have been easy to control with one anticonvulsant for 3 to 5 years.

The EEG can aid in the decision, with the presence of clear epileptiform activity before antiepileptic drug withdrawal or the return of epileptiform activity after withdrawal being a relative, but not absolute, contraindication. The best candidates for anticonvulsant withdrawal are those cases where the diagnosis of epilepsy may have been incorrect from the start.

Appendix I:  International Classification of Epileptic Seizures
Appendix II: Seizure Record
Appendix III: Examples of Naming Seizures
Appendix IV: Common Drug Interactions