Epilepsy Flashcards
Definition of a seizure
Abnormal firing of neurones manifesting as changes in motor control, sensory perception, behaviour and autonomic function
What is epilepsy?
Recurrent, spontaneous seizures arising from abnormal, synchronous and sustained electrical activity in the brain
What should be collected before diagnosing a patient with epilepsy?
Description of attack Family history Bloods ECG Medication history
What two tests can be used when diagnosing and classifying epilepsy and why?
MRI - to identify structural abnormalities
EEG - Classify the type of epilepsy (monitoring electrical activity in the brain)
What determines the types of epilepsy?
Area in the brain in which the seizure occurs
What are the types of partial seizures? Describe them (2)
Simple partial - General strange feelings, sometimes described as an aura, remain awake and aware
Complex partial - Loss of awareness accompanied by random body movements (smacking lips, hand/arm movements, random noises etc.), no memory of this seizure
What are the types of generalised seizures? Describe them (6)
Tonic - Muscles seize up, may lose balance and fall
Clonic - Shaking and jerking, may lose consciousness
Tonic-Clonic - Initial tonic stage, then body starts jerking (clonic stage), may have difficulty remembering
Myoclonic - Very quick, sudden twitch/jerk (like an electrical shock), normally aware
Absence - Short-term loss of awareness, may appear to be daydreaming or staring into space, unlikely to remember them
Atonic - Sudden relaxation of all muscles, may result in falling, generally able to resume normal activity soon after
What are common seizure triggers? (8)
Menstrual cycle Fatigue/Lack of sleep Stress Alcohol Flashing lights Excitement Missing meals Medication
What types of medication reduce seizure threshold? (8)
Quinolones SSRIs Tramadol Illicit drugs Tricyclic antidepressants Theophylline Antipsychotics Some penicillins
When would treatment for epilepsy be started and what is the general principle of treatment?
After second seizure
Start low, go slow
When would epilepsy treatment be initiated after a first seizure? (4)
If there is a neurological deficit present
EEG shows definitive epileptic activity
Risk of further seizure is considered unacceptable by patient
Brain imaging shows structural abnormality
When would adjunctive therapy be considered for epilepsy treatment?
If two first-line drugs have been tried as monotherapy
How should antiepileptics be switched?
Optimise second drug before withdrawing initial therapy
What should be done if combination therapy is not effective?
Revert back to regimen that has best seizure control
What can result from initiating antiepileptic therapy?
Suicidal ideation
What should all patients be given alongside antiepileptics?
Vitamin D supplements
What are MHRA category 1 AEDs and which drugs are included?
Have to prescribe same brand to prevent loss of seizure control
Phenytoin, carbamazepine, primidone, phenobarbital
What are MHRA category 2 AEDs and which drugs are included?
Decision to keep patient on same brand is down to clinical judgement
Clobazam, clonazepam, topiramate, valproate, esclicarbazepine, oxcarbazepine, rufinamide, zonisamide, perampanel, lamotrigine
What are MHRA category 3 AEDs and which drugs are included?
No need to keep patients on same brand
Ethosuxamide, lacosamide, gabapentin, pregabalin, levetiracetam, tiagabine, vigabatrin
What is antiepileptic hypersensitivity syndrome?
Rare but potentially fatal reaction to AEDs
Usually occurs within 1-8 weeks of initiating treatment
Symptoms - Fever, rash, liver dysfunction, lymphadenopathy, haematological/renal/pulmonary abnormalities, vasculitis, multi-organ failure
When could AED withdrawal be considered? How should this be actioned?
If 2 years seizure free
Under specialist, gradual withdrawal over 2-3 months, if combined therapy only one drug at a time
What should be done if a patient experiences seizures after AED withdrawal?
Reverse last reduction of treatment
What are the rules surrounding driving with epilepsy/seizures? (3)
Stop driving immediately -
If epileptic seizures (after diagnosis) - Can reapply after a year without seizures
If seizure was due to medication change or reduction - can reapply after 6 months seizure-free and on previous medication
If one-off seizure without epilepsy diagnosis - can reapply after 6 months if no seizures/medical advice states not high-risk of a recurrent seizure
What are the rules surrounding driving if having seizures whilst asleep/seizures that do not affect consciousness? (3)
Awake and asleep - If only seizures in past 3 years have been asleep, may still be able to drive
Asleep only - May still be able to drive if it has been at least 12 months since first seizure
Not affecting consciousness - May still be able to drive if these are the only type of seizures had and first was 12 months ago
Driving should still be stopped until appropriate guidance from the DVLA is received
What should be done if a woman diagnosed with epilepsy falls pregnant?
They should be registered on the UK Epilepsy and Pregnancy Register, regardless of AED treatment
If a woman diagnosed with epilepsy plans to get pregnant, what should they be treated with? Why?
5mg folic acid OD before conception and throughout pregnancy to prevent neural tube defects
What is the link between lamotrigine and hormonal contraceptives?
Reduced efficacy of contraceptives
Give 3 examples of AEDs which may need altering during pregnancy. Why?
Phenytoin, carbamazepine and lamotrigine
Plasma concentration of these may change during pregnancy
What should be monitored in pregnancy if on levetiracetam or topiramate?
Foetal growth
What can be done to reduce risk of neonatal haemorrhage?
Injection of vit K at birth
What are the most teratogenic AEDs?
Valproate and topiramate
What are the risk percentages associated with valproate and pregnancy?
10-11% risk of congenital defects
30-40% risk of neurodevelopmental defects
What is the risk associated with using topiramate in the first trimester of pregnancy?
Cleft palate
What should be used if under the pregnancy prevention programme?
ONE user-independent method or TWO user-dependent methods (incl. barrier method)
What can be done aside from PPP to reduce risks of valproate in pregnancy?(6)
Annual review Complete risk acknowledgement form Dispense in original packs Ensure pack has warning sticker and PIL Provide patient card at each dispensing Exclude pregnancy before intiating
What is the dosage of valproate? (initiation, titration and max)
Initially 600mg/day in 1-2 divided doses
Increase in steps of 150-300mg every 3 days to max. 2.5g/day
What are the cautions/contraindications of sodium valproate? (3)
Lupus Severe hepatic dysfunction Mitochondrial disorders (due to risk of liver toxicity)
Which systems do the main side effects of valproate arise from? (4)
Liver toxicity
GI side effects
Blood SEs (hypoNa/SIADH, blood dyscrasias, drug rash, SJS/TEN)
CNS SEs (aggression, headache, EPSE, suicidal ideation)
Give 3 random side effects of valproate
Hair loss (grows back curly)
Menstrual disturbances
Reduced bone mineral density
What are the monitoring requirements for valproate?
LFTs and FBC
Patient to report signs of blood disorders, liver disorders and pancreatitis
