GLOBAL CAMPAIGN AGAINST EPILEPSY
Bringing
EPILEPSY
Out of the Shadows
Specific objectives of the Global campaign against epilepsy
reduce the treatment gap and the physical and social morbidity of people suffering from epilepsy through intervention at community level
train and educate health professionals;
dispel stigma and promote a positive attitude to people with epilepsy in the community;
identify and assess the potential for prevention of epilepsy;
develop a model for promotion of epilepsy control worldwide and for its integration in the health systems of participating countries
Management of Epilepsy
Drugs are the mainstay of treatment in epilepsy
In recent times epilepsy can also be treated by surgery
In addition to this life style modifications are important in the management of epilepsy
Attitude/Compliance
Confirmation of epilepsy
Objectives of treatment are to control seizures with minimum side effects
To enable this the first step is to confirm whether the fit, faint or fall is indeed due to epilepsy.
Classification by the ILAE classification is mandatory prior to starting treatment
All fits, faints & falls may not be epilepsy.
Cardiac disorders like aortic and mitral stenosis, Stokes Adams attacks, cardiac arrhythmias may cause syncopal attacks.
Beware of pseudoseizures
To treat or not to treat
Once a diagnosis of epilepsy is made, the question of whether to treat or not arises.
Recurrence rates after a single seizure (GTCS) vary from 16-61%.
After two tonic clonic seizures, the risk of having a third seizure rises to about 85%..
Risk factors for seizure recurrence
prior brain injury
abnormal neurological examination
epileptiform abnormalities on the EEG
occurrence of postictal or Todd paralysis
status epilepticus
a family h/o seizures
and acute symptomatic seizures caused by head trauma.
Classification
generalized
simple partial
complex partial
an epileptic syndrome
localisation related epilepsy
nonepileptic attack disorder
Seizure classification
Choice of drug according to seizure type is based on
the mechanism of action of the drug
traditionally established efficacy of some drugs in certain types of seizures.
Monotherapy vs Polytherapy
Having decided what drug to use, monotherapy with the first line drugs is preferred in most patients.
Polytherapy may have to resorted to in some patients
Drugs should be appropriately combined, taking into account drug interactions, side effects, mechanism of action,etc as rational polytherapy
Advantages of monotherapy
Equal or superior efficacy to many two or three drug regimens
Reduced frequency of adverse effects
Lack of drug interactions between antiepileptic drugs
Increased ability to correlate drug response, adverse effects, and laboratory values to a specific drug
Reduced risk of birth defects when used in women of child bearing age
Improved compliance – this is important as noncompliance is the most common cause of drug failure and breakthrough seizures
Age & Sex of the patient
The same drugs are used to treat both children and adults, but the pharmacokinetics and side effect profiles of the drugs can differ.
Many drugs such as phenytoin, need to be given in proportionately higher doses to achieve therapeutic levels in young children.
Also, drugs that cause one type of side effect in adults (sedation) may cause opposite effects (hyperactivity) in children.
Age & Sex + Other factors influencing drug choice
Phenytoin affects calcium metabolism and can interfere with growth, hence would not be a first choice in a young children.
In the elderly, one has to be alert to drug interactions between antiepileptic drugs and co medications such patients may often be taking for other illnesses.
In women, the teratogenic potential of a drug may influence the choice of drug.
Another precaution is to choose relatively nonsedating drugs in patients handling machinery, etc
Drug related factors
The mechanism of action of an AED
its plasma half life
the range between peak and trough blood therapeutic levels can influence the daily level and timing of dose of the drug
interactions during polytherapy
potential for teratogenicity, etc
Mechanisms of actions of anticonvulsants
Sodium pump – Phenytoin +++/ Carbamazepine +++/Phenobarbitone++/Valproate++
Calcium ion – Valproate +/ Ethosuximide +++
When sodium dependant ion channels are dampened, sustained high frequency neuronal firing is reduced and calcium uptake and excitatory neurotransmitter release is decreased
Some drugs directly facilitate GABA eg Benzodiazepines, Phenobarbitone, Valproate
Ethosuximide reduces slow rhythmic firing of thalamic neurons
The ultimate effect is to enhance the inhibitory GABA or reduce the excitatory glutamate
|
