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Epilepsy
Contents:
Classification of epileptic seizures in adults
Incidence and prevalence
Drugs of choice for the treatment of epilepsy
Counselling points for patients with epilepsy
Who needs referral?
Anti epileptics and oral contraceptives
Pregnancy
Monitoring tests required with patients with antiepileptic
drugs
Epilepsy and Driving.
Some references regarding epilepsy and general practice
Classification of epileptic seizures in adults
1. Partial seizures
A. Simple partial (no alteration of consciousness)
Results from focal epileptic discharge in a localised part of the brain. A simple partial motor seizure begins in the motor
cortex. When it spreads sequentially through the motor strip, it is called a Jacksonian march.
B. Complex partial (with alteration of consciousness)
A prodrome is common and automatisms are seen in 90% of patients, with post ictal drowsiness in 75% of patients.
C. Partial becoming secondarily generalised (secondary generalised tonic-clonic seizures)
A partial seizure which spreads to the entire brain to produce a convulsion is a secondary generalised seizure.
2. Generalised seizures
A. Absence
A brief episode of unconsciousness with little or no motor accompaniment. (petit mal).
B. Myoclonic
Usually single, sudden, uncontrollable jerks.
C. Clonic
D. Tonic
E. Tonic-clonic
An epileptic attack in which there is loss of consciousness and generalised tonic then clonic muscle contractions.
F. Atonic
An attack in which there is generalised loss of muscle tone, and the patient falls down. Consciousness is not lost.
Incidence and prevalence

Incidence 25 to 50/100,00 per year

Age dependant (high in children low in adults and increased in elderly)

Prevalence 0.5%

Average GP will care for about 10 patients who are being actively treated, 2-3 will continue to have fits despite
treatment.
NB there is an increased incidence of sudden unexpected death (x6) not entirely due to status epilepticus.
Drugs of choice for the treatment of epilepsy
1st choice
Partial +/- SGTCs*
Probable second choice Last resort
Phenytoin
Carbamazepine
Vigabatrin
Sodium Valproate Lamotrigine
clobazam
Lamotrigine
Primary Generalised
Carbamazepine
Sodium valproate
Tonic-Clonic
Phenytoin
Clobazam
Absence
sodium valproate Lamotrigine
Ethosuximide
Clobazam
Myoclonic
Lamotrigine
sodium valproate Ethosuximide
Clobazam
Phenobarbitone
Primidone
Phenobarbitone
Primidone
*SGTCs=Secondary generalised tonic clonic seizures
Counselling points for patients with epilepsy
1. Poor compliance is the most common cause for treatment failure
2. Patient must not run out of medication
3. Continue antiepileptics throughout illness, take an extra tablet if vomiting occurs soon after taking a tablet.
4. Medication should be taken regularly, as missed doses may provoke seizures
5. Encourage the use of a seizure diary.
6. Counsel patients on the use of contraceptives
7. Alcohol



acute withdrawal of alcohol may induce a fit
alcohol is an enzyme inducer and may alter drug levels
sedative properties are potentiated
8. Encourage patient to report side effects
9. British epilepsy Association
Who needs referral?
Reasons for referral
a. To confirm the diagnosis

About 20% of patients referred to a specialist epilepsy clinic do not have epilepsy

The diagnosis of epilepsy carries with it considerable implications

NB recent BMJ leader (Sander at al BMJ 1997 vol 314) summarised the situation that not all patients that
convulse have epilepsey other diagnoses including syncope, non-epileptic attack disorder (hysterical fitting)
and early <2mins post concussive fitting following a head injury, eg in the sports field. They suggest that every
effort should be made to reach a firm diagnosis but that if doubt remains that it is usually wise to await further
events and secure a diagnosis than to initiate anti epileptic therapy
b. Choice of treatment is changing all the time therefore up to date opinion is required
c. Advice about driving, employment, schooling etc..
Most common complaint of patients is lack of information
d. Patients with special circumstances e.g. pregnancy(see later)
e. Patients with continuing seizures
Diagnosis must be reconsidered
20% of patients with drug-resistant epilepsy have emotional attacks or non epileptic attacks.
Use of video telemetry and EEG are invaluable
Anti epileptics and oral contraceptives
The effectiveness of both combined and progestogen only contraceptives may be considerably reduced by interaction
with drugs that induce hepatic enzyme activity.
Anticonvulsants that induce hepatic enzyme activity:
phenytoin

carbamazepine

phenobarbitone

primidone
Loss of efficacy does not appear to be a problem with:
sodium valproate

vigabatrin

lamotrigine

gabapentin

bendodiazepines
However with the introduction of all anticonvulsants the patient should be asked to report any changes in the
menstrual cycle
Family Planning association advises that in women who are unable to use an alternative form of contraception that a
50microgram pill be used.
If breakthrough bleeding occurs despite this either increase the dose of oestrogen or use a different form of
contraception
Some feel that an additional form of contraception should be used, others feel that this is only necessary when
adjustments are made in the anticonvulsant dose.
Depo-provera
No problems reported by the manufacturers
Pregnancy

Despite the risks, with preconception counselling and careful management throughout the gestation >90% of
women with epilepsy can have a successful pregnancy and healthy baby

Abnormalities can occur with all main antiepileptic drugs

Avoid polypharmacy esp. combination of valproate,phenytoin and phenobarbitone
The risk of major malformations, minor anomalies and dysmorphic features is x2-3 higher in infants of mothers with
epilepsy who receive treatment with epileptic drugs compared with the risk in infants of mothers without epilepsy
A possibility exists that some of the risk is caused by a genetic pre-disposition for birth defects inherent in certain
families and therefore genetic counselling may be required
Possibilities for prenatal diagnosis of major malformations should be discussed. High resolution scanning can be done at
16-22 weeks gestation.
The effects of tonic-clonic seizures are not well studied but they may injure the mother and may result in miscarriage
All women contemplating pregnancy should take folic acid 5mg/day
I thepatient has been seizure free for at least 2 years, withdrawal of anticonvulsant should be considered
If anticonvulsant treatment is necessary then a switch to monotherapy may be necessary
The lowest dose and plasma level should be used.
Monitoring tests required with patients with antiepileptic drugs
Drugs/Drug group Monitoring required
Drugs/Drug group Monitoring required
Carbamazepine
Check blood levels only if there are continuing seizures or side- effects or to check compliance. FBC
an LFTs before treatment and then regularly.
Phenytoin
Check blood levels only if there are continuing seizures or side-effects or to check compliance. FBC
an LFTs before treatment and then regularly. Check folic acid levels every six months
Barbiturates
Check blood levels only if there are continuing seizures or side-effects or to check compliance
Valproate
FBC an LFTs before treatment and then regularly. Blood concentrations are not clinically useful
Lamotrigine
Gabapentin
Vigabatrin
Clobazam
No routine motoring is required
If a patient is well controlled there is no reason to check levels and if they are checked do not increase dose just to get it
within the therapeutic range!!!
Epilepsy and Driving.
The
law
and
medical
fitness
to
drive--a
study
of
doctors'
knowledge.
Doctors' knowledge on laws and recommendations regarding fitness to drive in certain medical conditions by a
questionnaire survey. The results show the poor knowledge of doctors on several aspects of fitness to drive.
Postgrad Med J 1992 Aug
Regulations updated in 1994; Licence may be granted for 1,2 or 3 years provided
a) Free from any epileptic attack during the period of 1 year prior to the date of issue
OR
b) Nocturnal attacks only for 3 years
AND
c) Driving is not likely to be a source of danger to others
Licence may be changed to a 'till 70' if 6 years seizure free.
Medical Advice
Must be quite clear
1. Patient must be told he has epilepsy and that the law will prevent him from driving.
2. Emphasise to the patient that he must inform the DVLA.
3. Continued driving is illegal and may invalidate insurance cover.
4. Doctor has no legal responsibility to inform the DVLA
Must keep a written record
Confidentiality
A doctor should observe the code of professional conduct
GMC recognises that confidentiality may be breached where in the public interest failure to do so may place the patient
or some other person at risk of serious harm or death.
In the first place the doctor must advise the patient to inform the DVLA
Subsequently he should challenge the patient and inform him that the doctor will have to inform the DVLA and WHY.
This must be documented
If the patient does not inform the DVLA then the doctor should now do so.
If the doctor is aware that the DVLA had revoked the licence but the patient continues to drive the doctor may inform
the police
Withdrawal of anticonvulsants.
There is a 40-50% risk of seizure recurrence in the succeeding 2 years
Most commonly as drugs are reduced and for six months after they have been stopped
Therefore under these circumstances it is advisable that the patient does not drive whilst the dose is being reduced and
for six months after. But this is not enforced by the DVLA not is it a legal requirement.
Patients should also be aware that if they do have a seizure they will then be barred for a year after their last seizure
Isolated seizure
Defined as one or several seizures occurring in less than 24 hours
Patient must inform the DVLA
The licence will normally be revoked for one year or seizure free for 12 months.
If the seizure has been provoked e.g. drug abuse then the cause may be more relevant
Vocational drivers
Must be free
1. Epileptic attacks for >10years
AND
2. Have not taken anticonvulsants for 10 years
AND
3. Do not have a continuing structural cause.
Some references regarding epilepsy and general practice
BJGP review Thapar: Care of patients with epilepsy in the community. BJGP Jan 1996
Literature study using Medline and Epidata
Specific problems and difficulties of managing patients with epilepsy in the community can be categorized as :
1. Lack of systematic follow up
Many reviews suggest that patients are not regularly followed up by either their GP or the hospital. The reasons for this
haven't been explored and the effectiveness of systematic follow up needs to be researched.
2. Inappropriate polypharmacy
Studies show that between 35 to 60% of patients are on more than one drug
Optimum seizure control can be achieved for 70-80% of patients.
Polypharmacy increases side effects, may not be efficacious, reduces compliance and makes monitoring more difficult
3. Pt non compliance
50-70% of patients are compliant with med. from pt reporting and blood monitoring
Patients often decide to not comply due to stigma associated with treatment.
Need to discuss compliance and the possibility of stopping treatment with patients.
4. Failure of GP - pt communication
Studies have shown communication to be suboptimal. Many patients feeling they require more in formation than is
given by their GPs
5. Low levels of pt knowledge
One study suggested that patients with epilepsy had the same knowledge about their condition than controls!!
Barriers to effective community care
1. Oganisational barriers
Computer searches fast but may be inaccurate e.g. some patients are taking anticonvulsants for conditions other than
epilepsy
Notes review and interview, more time consuming
Call recall is often difficult and defaulters may be the most in need of follow up
Practice based epilepsy specialist nurses are advocated but a costly resource.
2.GP related barriers.
Reports suggest that most GPs feel that epilepsy is a complex disorder to manage.
3. Patient related barriers
Stigma felt by patients is often greater than the stigma enacted upon them by others.
Stigma increases with the severity of the illness
Stigma increases withdrawal and reduces attendance at special epilepsy clinics
Some patients do not have confidence in their GPs management of patients.
Initiatives to improve care for patients with epilepsy in the community
Local initiatives
Very little work on:
Practice based clinics
Epilepsy specialists nurses working in GP practices
Liaison nurses, between prim and sec care but also as an information base for GPs
Guidelines have been produced in certain regions e.g. by the Irish RCGP
National initiatives
Two recent initiatives sponsored by Wellcome
1. Epilepsy task force
multidisplinary group and patients group-s
Aims
to raise public awareness
lobby for appropriate primary and secondary care provision
establish guidelines and minimum standards for hospital OPD services
2. Epilepsy liaison nurse programme
Ran for a year in areas where there were specialised clinic
Helped GPs manage their patients
Helped GPs set up clinics and audit their care
Have not been fully evaluated
Epilepsy monitoring and advice recorded: GP's views, current practice and pt's preferences GP study of 37 GPs and
283 patients with epilepsy. BJGP 1996,46,11-14 Risdale et al
The majority (61%) of pt preferred their care to be supervised by their GPs
GPs reported that patients should be reviewed every 6 months (median 14 months)
GPs felt that a record should be made in the notes of the following in all patients:
Information
% of notes with information recorded
Driving regulations 46
Drug side effects
9
Self help groups
3
35% of patients reported not getting enough advice.
A general practice records audit of the process of care for people with epilepsy.
AIM: The study was designed to examine the process of care for people with epilepsy through a region-wide audit of
general practitioner records. METHOD: General practitioners in 31 randomly selected general practices in one UK
health region undertook a notes audit for all patients identified as having active epilepsy (patients who had had
seizures in the last 2 years, or were currently seizure-free but on antiepileptic medication). A standard pro forma was
used to collect information relating to diagnosis, drug treatment, and primary and secondary care contacts. RESULTS:
Recording of information in the notes was generally good, but poor for some key items essential to the effective
management of the condition; results suggest that a number of recommendations about provision of care for epilepsy
are not being met: in particular, EEG and CT investigations often appear poorly directed; prescribed antiepileptic
therapy is not always optimal; significant numbers of patients are being treated in hospital by non-neurologists; there is
little evidence of any regular review being undertaken by general practitioners of their patients with epilepsy; and
counselling about the non-clinical aspects of epilepsy often appears inadequate. CONCLUSIONS: Despite
recommendations in a number of recent reports, gaps and inconsistencies in epilepsy care persist, both at the primary
and secondary level. The means by which such shortcomings can be reduced (e.g. by specialist epilepsy nurses working
across the primary-secondary care interface) should now be systematically examined. The study has highlighted a need
for evidence-based guidelines which span the primary-secondary care interface and clarify the contribution of the
various practitioners involved in the provision of care for people with epilepsy.
Jacoby A Br J Gen Pract 1996 Oct 46
Francisco Machado 1/4/1997