Monday, August 13, 2007

INFORMATION ON EPILEPSY & AEDs

Epilepsy is a much misunderstood medical disorder, inspite of the illness being known to mankind for over 3000 years. There are many myths and fears about this eminently treatable condition. One of the common myths is that epilepsy is a mental illness which is not so.
We now know that with the available antiepileptic drugs, epilepsy can be well controlled in about 75 to 80% of patients and the drugs can be withdrawn if a person is fit-free for to 2-5 years period. However the disease which can be so well controlled is perceived as a great setback and great cause for misery, simply because of the wrong notions. To make matters worse the doctors have very little time to convey the total picture of epilepsy and they concentrate more on procedures and prescription of the drugs. In order to facilitate patients to gain information about various non-medical aspects of epilepsy, an organization known as International Bureau for Epilepsy (IBE) was formed in 1961 by Mr. George.Burden who was a non-medical person and who recognized the necessity of such an organization.

As written by Dr. K.K. Sinha


Dr. B S Singhal, Prof & Head - Dept of Neurology

Epilepsy is common. The treatment goal is to achieve total freedom from epileptic epileptic attacks. Failure to comply with treatment regimes is a common cause of seizure recurrence. In this case of antiepileptic drugs ( AEDs) non compliance means not taking the drug or not taking the recommended dosage or not taking the drug for the duration specified. Besides, there may also be noncompliant behaviour such as not altering the life style activities known to trigger seizures ( e.g not getting enough sleep and overindulgence in alcohol )
There can be several reasons for non compliance. Failure to educate the patient regarding the nature of illness, the drugs prescribed with their side effects and the need for regular and prolonged medication is an important cause for noncompliance. Regrettably this aspect is often neglected in our country. Being busy in patient care cannot be an excuse. Also the patients seek multiple consultations and the new doctor may presume that the patient has been briefed by the previous physician. In the past availability of the AED was an issue. Today a particular brand may not be available at all places. It would therefore be desirable to write the generic name and alternative brand names so that the patient gets the drug. The high cost of the drug can be a factor for discontinuation of AED and this should always be taken into consideration. Frequent dosing can be another cause for missing the drug, especially the afternoon dose. Fortunately many drugs are now available with controlled release preparations which enable them to be given in a convenient single or twice a day schedule. Complex drug regimens withmultiple drugs ( at times result in missing the all important AED. Patients also tend to become noncompliant when they feel better due to a good seizure control. On occasions, the patients discontinue the drug to see is they are cured. Fortunately in India the mother ensures that the child is given the drug at the scheduled time, but there can be a lapse on the part of the teenagers and mildly forgetful elderly patient.
Many a patient has apprehension about the long - term toxicity of AED which need to be dispelled. In particular, newly married women may have fear regarding the effect of AED on fertility and pregnancy and they need proper counseling. Regrettably too often, the firls get married ( in case of arranged marriages ) without disclosing the illness. After marriage the girl tries to avoid taking the drug at the scheduled time or in appropriate dose resulting in seizure recurrence. Many patients in India have faith in ayurvedic or homeopathic medication. Practitioners or alternative medicine often gives false assurance to the patients of achieving a ' cure' from epilepsy. There is unfortunately no governmental control for such persons. The results in switching to other drugs with recurrence of the seizures.
To conclude, non compliance is a major factors in seizure recurrence. In such a case, one should always enquire if the individual has missed the drug before escalating the dose or switching to another drug. One may also get some idea regarding non compliance by doing the pill count and going serum drug level. We can hope to achieve better seizure control by improving compliance through education of the patient, use of memory aids such as pill boxes, reinforcing good physician - patient relationship, by providing good family support, and help from the support groups.


Dr Sunil K Pandya, Neurosurgeon
Drugs used in the treatment of epilepsy in India : need for reappraisal
Fashions in drug therapy
There has been a marked increase in the number of drugs available for the treatment of epilepsy and new drugs are being added each year. At first sight this appears to be a reason for celebration. Drug companies introducing the latest drugs certainly lost no time extolling their virtues and marketing them aggressively to doctors likely to use them. Doctors, keen to follow the dictates of fashion, soon switch over from old, time-tested chemicals to the drug that is the ' flavour of the month'. In this in the best interests of patients ?
Drug manufacturers spend small fortunes highlighting the superiority of their latest offerings over those of rivals and denigrating the now unfashionable older drugs. Unfortunately, the majority of doctors accept what is dished our to them by the companies, their critical faculties having been dulled by years spent without visiting a medical library or studying recent issues of indexed medical journals. Sweeteners offered by pharmaceutical companies make acceptance easier. Visit any annual conference and you will see a variety of gifts on offer to doctors. These range from bags to suitcases, to trips, to tourist attractions within the state where the conference is being held. These companies also host liberal cocktail parties and gala dinners. Blatant advertisement of new drugs on conference screens and all around conference halls is not the norm.
The patient pays the price in more ways than one.Newer drugs are invariably much more expensive then those of yesteryear. Manufacturers are now reluctant to produce the 'cheap' drug, as the profit margin on them is much lower then that on the latest product. Over time, costs o f patients escalate as the inexpensive drugs become 'orphans' and are phased out.
The side effects or 'adverse reactions produced by drugs in use over decades are well documented, understood and easily detected. The unwelcome effects produced by the newer drugs are underplayed by the manufacturer and are poorly understood by the doctors. It is years before these become public knowledge in the medical fraternity. As a consequence, they may be missed. This is harmful to the patient. By the time these side-effects become public knowledge, the company has made profits from this drug and has shifted its spotlight on to its latest offering.
Why is a reappraisal of the prescription of drugs against epilepsy necessary ?
Most of our patients are poor. It is unfair to them and their families to foist expensive new drugs on them when an older preparation will suffice to control fits without causing harm. A case in point is the adult whose fits are controlled by phenobarbitone tablets without any side effects. Why should a more modern expensive drug be substituted in his case ? Why should phenobarbitone or phenytoin not be tried as the first drug when its use is appropriate on medical grounds ?
Where possible, the inexpensive drug must be preferred provided it is equally effective and causes no harmful effects.
The newer drugs against epilepsy - like new antibiotics - must be reserved for use in those patients where the older drugs are ineffective or have caused complications. The use of sodium valproate in a patient in whom phenytoin has produced the Steven-Johnson syndrome is unchallengeable.
New epilepsy prevention study findings have been reported by scientists at University of Bonn
August 10, 2007
Pain & Central Nervous System Week via NewsEdge Corporation :
2007 AUG 13 - (NewsRx.com) -- Investigators publish new data in the report "Diminished response of CA1 neurons to antiepileptic drugs in chronic epilepsy." According to a study from Bonn, Germany, "A substantial proportion of epilepsy patients (approximately 30%) continue to have seizures despite carefully optimized treatment with antiepileptic drugs (AEDs). One key concept to explain the development of pharmacoresistance is that epilepsy-related changes in the properties of CNS drug targets result in AED-insensitivity of these targets."
"These changes then contribute to drug-resistance on a clinical level. We have tested this hypothesis in hippocampal CA1 neurons in experimental epilepsy. Using patch-clamp techniques, we thoroughly examined the effects of carbamazepine (CBZ) and phenytoin (PHT) on voltage-gated Na( ) currents (I(Na)) in hippocampal CA1 neurons of sham-control and chronically epileptic rats. We find that there were significant changes in the effects of PHT, but not CBZ on the voltage-dependence of inactivation, resulting in a significant reduction in voltage-dependent blocking effects in chronically epileptic animals. Conversely, CBZ effects on the time course of recovery from inactivation of I(Na) were significantly less pronounced in epileptic compared to sham-control animals, whereas PHT effects remained unaltered. Our findings indicate that AED-sensitivity of Na( ) currents is reduced in chronic epilepsy. The reduction in sensitivity is due to different biophysical mechanisms for CBZ and PHT. Furthermore, comparison to published work suggests that the loss of AED-sensitivity is less pronounced in CA1 neurons than in dentate granule neurons. Thus, these results suggest that target mechanisms of drug resistance are cell type and AED specific," wrote C. Schaub and colleagues, University of Bonn.
The researchers concluded: "Unraveling these complex mechanisms is likely to be important for a better understanding of the cellular basis of drug-resistant epilepsy."
Schaub and colleagues published the results of their research in Epilepsia (Diminished response of CA1 neurons to antiepileptic drugs in chronic epilepsy. Epilepsia, 2007;48(7):1339-50).
For additional information, contact C. Schaub, University of Bonn Medical Center, Dept. of Epileptology, Bonn, Germany.
The publisher of the journal Epilepsia can be contacted at: Blackwell Publishing Inc., 350 Main St., Malden, MA 02148, USA.