Health news blog » Epilepsy

MEDICAL TREATMENT OF SEIZURES: PHILOSOPHY OF TREATMENT

admin — Fri, 13 May 2011 13:10:41 +0000

Although once it was believed that all seizures should be treated, just because they were there, now it is generally believed that no judgment can cover every individual. Decisions about treatment should be made by the patient (or parent) and the physician acting in partnership. The decision should be based on risk-benefit analysis.
The risks and consequences of each medication vary with the medicine, with the dose, with the individual’s reaction to the medicine, with the age of the child, and with the length of time the child takes the medicine. The risk of further seizures varies markedly with the type of seizure, the frequency of seizures, and even the time of day in which they occur. A child who has only occasional tonic-clonic seizures at night will face very different risks from a child whose seizures occur during the day. A child with occasional complex partial seizures has different risks from the child with tonic-clonic seizures or the child with frequent absence seizures.
Most people’s seizures can be controlled with a single medicine used in a proper dose to achieve a proper blood level for that individual. There is no correct dose of a given medication. The “proper” dose of medication is the dose that completely controls the seizures without causing significant side effects. There is not a “correct” medication as such. Some medicines work better for some types of seizures than for others. The correct medicine is the one that works.
The treatment of epilepsy is empirical. This means that the treatment of each person’s seizures is a trial or search to find the appropriate dose
of the best medicine for that individual. This “experimentation” is often frustrating to parents since they are used to physicians’ knowing, for example, the right antibiotic and dose to use for a child’s ear infection.
For drugs like antibiotics, we know how they act, the proper dose, and the side effects. We know how much is necessary to kill the bacteria causing the infection. We can test the drug’s effectiveness in the laboratory. We know, for example, how “heart drugs” work and their side effects, we can use the electrocardiogram (EKG) to see if they are working or if they are producing toxicity. But, since we do not fully understand how anticonvulsant drugs work, and since we do not understand the factors that permit a seizure to occur at a specific time, each child must be his own laboratory as a doctor attempts to find the proper dose of the best anticonvulsant. Side effects will vary with each child’s metabolism and his individual reaction to the drug.
*105\208\8*

SEIZURES AND EPILEPSY IN CHILDHOOD: UNDERSTANDING YOUR CHILD’S TESTS – SPIKES

admin — Mon, 14 Feb 2011 15:39:21 +0000

Since a clinical seizure requires that a sufficient number of brain cells fire together to cause the alteration in movement or behavior, one would expect this “firing” to cause a change in the electrical activity recorded on the EEG. That is exactly what does happen. The normal EEG represents an almost random firing of brain cells; when the cells fire simultaneously they produce an electrical abnormality in the EEG called a “spike”.
A spike is a mini-electrical seizure. Only if that electrical disturbance spreads to involve more cells (a sufficient number to change behavior) would a true clinical seizure occur. Thus, repeated spikes coming from a particular area represent the local response to a provocation there, an epileptic focus or scar. In a child (or adult) who has had a focal seizure, spikes may indicate the area of the brain where the seizure started.
Multifocal spikes, by comparison, suggest that there are many abnormal areas of the brain.
Spikes are not of significance unless they are found consistently in one area.
*78\208\8*

EPILEPSY: THE FACTS-STOPPING ANTI-EPILEPTIC MEDICATION

admin — Tue, 28 Apr 2009 12:38:19 +0000

Children with epilepsy and their parents, and adults with epilepsy obviously want to know when it is sensible to stop anti-epileptic medication when they have been free of seizures for two or three years. What risks of recurrence do they have, and should they stop the drugs very slowly, or does the speed with which they do this matter very much? 20 years after diagnosis, 50 per cent of a community sample will have been free from all seizures without anti-epileptic drugs for at least five years, and many will have abandoned their drugs far earlier. What advice can be given?

First of all, it must be recognized that many people are anxious about the possibility of recurrence of seizures, not least because if one occurs, a driving licence regained will be lost again for one year. However, it seems sensible to try and avoid potential adverse effects from very long-term use. In children, there may be anxieties about continued medication and potential effects on cognitive function and learning. Women in their child-bearing years may be anxious about the possible effects of anti-epileptic drugs upon the prenatal development of their babies.

Factors which indicate a significant risk of relapse of seizures on stopping anti-epileptic drugs include the epilepsy syndrome (juvenile myoclonic epilepsy being particularly likely to relapse), and the duration of epilepsy, the number of tonic-clonic seizures so far, and the need to take more than one anti-epileptic drug before control was established. All these factors, if present, suggest ‘difficult’ epilepsy, so it is not surprising if seizures recur if anti-epileptic drugs are stopped.

The EEG may occasionally be helpful about deciding when to withdraw drugs but only in children, in whom it has been shown that the presence of persisting generalized spike-wave activity makes relapse more likely. The evidence is much less impressive in adults,

Top curve: probability of completing a period of five consecutive years without seizures. For example, six years after diagnosis 42 per cent of patients have been seizure free for five years.

Middle curve: the probability of being in remission, at any time, for at least the past five years. The difference between the top and middle curve is due to relapse after achievement of a five-year remission. For example at 20 years after diagnosis 70 per cent of patients are currently free from seizures and have been for five years and a further 6 per cent have had at least one seizure-free period of at least five years’ duration, but have subsequently relapsed.

Lowest curve: the probability of being free of seizures for at least five years whilst not taking anticonvulsant drugs.

In summary, 20 years after diagnosis 50 per cent of patients were free from seizures without anticonvulsants for at least five years. A further 20 per cent continue to take anticonvulsant medication and have also been free of seizures for at least five years. Seizures continue, in spite of medication, in 30 per cent. Data from Dr J.F. Annegers and colleagues.

But it may be assumed that a markedly abnormal EEG, by indicating widespread nerve cell abnormalities, makes it rather more likely that further seizures will occur. However, the finding of any abnormality does not imply that seizures necessarily will recur, and the absence of any abnormality does not guarantee that seizures will not recur. For this reason, many specialists do not carry out an EEG before stopping treatment, but decide on the basis of the type of seizure or epilepsy syndrome that the patient has and the interval that the patient has been seizure-free.

It is generally felt, if a decision is made to withdraw anti-epileptic drugs, this should be done gradually over about two-three months or so. This is particularly important for phenobarbitone and for the benzodiazepine group of drugs (for example, diazepam or Valium and clobazam frizium) of drugs; in patients taking these drugs, abrupt withdrawal may precipitate a burst of seizures, rather like what is known to happen in someone who suddenly stops drinking after many years of abusing alcohol.

*73\188\2*