Clinical CNS Epilepsy Flashcards

(132 cards)

1
Q

Define epilepsy from ILAE (international league against epilepsy):

A

A disease of the brain defined by any of the following conditions:
-at least 2 unprovoked (or reflex) seizures occurring more than 24hrs apart
-one unprovoked (or reflex) seizure and a probability of further seizures similar to the general recurrence risk after 2 unprovoked seizures (60%) over next 10 years
-diagnosis of epilepsy syndrome

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2
Q

What is convulsive status epilepticus?

A

The prolonged convulsive seizure lasting 5 mins or longer or recurrent seizures one after the other without recovery in between

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3
Q

Describe the location epidemiology of epilepsy:

A

Affects 70mil people worldwide and UK is thought to be 5-10/1000
Close to 80% of these people live in low-middle income countries, due to:
-indemic conditions, malaria, high traffic injuries, birth related injuries, 75% not receiving correct treatment

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4
Q

What is the person epidemiology of epilepsy?

A

Can affect people of all ages, race and gender
Highest in infants and people over 50
People who have learning difficulties also have higher rates of epilepsy in comparison to general population

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5
Q

Describe the mortality in epilepsy:

A

Increase risk of premature death in pts with epilepsy
Epilepsy related deaths are thought to be caused by:
-epileptic condition
-anti-epileptic condition
-co-morbidities
-unexplained- SUDEP

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6
Q

What is SUDEP?

A

Sudden Unexpected Death in Epilepsy
Most cases are thought to occur after a seizure
Normally happens unwitnessed at night whilst asleep

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7
Q

What are the risk factors for SUDEP?

A

Tonic seizures
Night time seizures
Not being on anti-epileptic drugs

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8
Q

Describe the aetiology of epilepsy:

A

2/3 of pts have unknown cause (idiopathic)
Structural- visible abnormalities in the brain using neuroimaging e.g stroke/trauma
Genetic- dravet syndrome
Infectious- infection where seizure is core symptom e.g TB, cerebral malaria
Metabolic- perforia, pyridoxine deficiency
Immune- evidence of AI mediated CNA inflammation, anti-NMDAr encephalitis

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9
Q

What are the risk factors for epilepsy?

A

Premature birth
Complicated febrile seizures (brought on by high temp)
Brain development malformation
FH of epilepsy or neurological disease
Head trauma
Infections (e.g meningitis and encephalitis)
Tumours
CVD/stroke
Dementia and neurodegenerative disorders
Drugs and alcohol withdrawl

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10
Q

What is the process for diagnosing epilepsy?

A

Referral to a specialist in epilepsy- all adults and children with first seizure should be seen asap
Detailed history from the pt and eye witness attack can help determine whether it was an epileptic seizure or not- recordings helpful

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11
Q

What are the investigations carried out when diagnosing epilepsy?

A

EEG (electroencephalogram)- to support diagnosis
Blood tests, U&E, ECG
Neuroimaging (MRI,CT)
Genetic testing (informed consent)
Antibody testing- new onset epilepsy if AI encephalitis suspected
Neurophysiological assessment- evaluate learning disabilities

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12
Q

What are the classifications of epilepsy?

A

Seizure type
Epilepsy type
Epileptic syndrome

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13
Q

What are the different seizure types?

A

Focal
Generalised
Unknown

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14
Q

What are the different epilepsy types?

A

Focal
Generalised
Combo
Unknown

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15
Q

Describe the classification of epilepsy in neonates:

A

Most common neurological emergency in neonatal period
Often provoked by an acute cause
Different classification as doesn’t fit into classifications for older children/adults
EEG used for diagnosis (gold standard)

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16
Q

How does ILAE classify seizures?

A

Classify due to humorous factors:
-where seizures start in the brain
Level of awareness pt had of seizure
Whether or not other symptoms e.g motor

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17
Q

What are focal seizures?

A

Increase in neuronal activity originating and remaining in one hemisphere of the brain
These are then subdivided into level of awareness:
-simple focal seizures (no loss of consciousness)
-complex or focal dyscognitive seizures (impaired awareness)

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18
Q

What are the aware+ impaired motor symptoms of focal seizures?

A

Automatisms (repeated/automatic movement)
Atonic (loss of muscle tone)
Clonic (jerking)
Epileptic spasms (extending of muscles in trunk/ close to trunk)
Hyperkinetic (irregular big movements)
Myoclonic
Tonic (stiffness)

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19
Q

What are the aware+ impaired non-motor symptoms of focal seizures?

A

Autonomic (changes in HR, breathing, colour)
Behaviour arrest (blank stare, stop talking/moving)
Cognitive (confusion, slowed thinking, problems talking)
Emotional (sudden fear, dread, anxiety, pleasure)
Sensory (change in vision, taste, tingling, pain)

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20
Q

What is the name of seizures have a focal onset but spread to other areas of the brain?

A

Focal to bilateral tonic clonic seizures

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21
Q

What is the difference between generalised and focal seizures?

A

Level of awareness isn’t looked into as much as with generalised the majority (not all) of these seizures have impaired awareness

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22
Q

What are generalised seizures?

A

Increase in neuronal activity that is widespread across both hemispheres of the brain, these are subdivided into:
-motor symptoms (physical movement)
-non motor aka absense (no physical movement)
-unknown onset- not sure where in the brain it starts
-unclassified- insufficient info to identify seizure type or nature of seizure

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23
Q

What are the motor symptoms in generalised seizures?

A

Tonic
Myoclonus
Atonic
Clonic
Tonic-clonic (ONLY IN GENERALISED)

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24
Q

What is tonic movement?

A

Sustained increase in muscle contraction (tense and rigid muscles)

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25
What is myoclonus movement?
Muscle twitching (can involve single or multiple muscle groups)
26
What is atonic movement?
Muscle becoming limp (opposite to tonic)
27
What is clonic movement?
Jerking, rhythmic twitching movements
28
What is tonic-clonic movement?
Where the seizure starts off in tonic phase (muscle rigidity, loss of consciousness, rest stops, involuntary crying) into clonic phase where you have muscle twitching- relaxing and contracting with loss of control of bladder and/or bowels After the seizure, some people will get a post ictal phase
29
What is a post ictal phase in seizures?
They have trouble remembering what has happened, feels tired, confused
30
What is absence in the non-motor symptoms?
Vacant starting, movement stops
31
What is epilepsy syndrome?
Epilepsies with specific signs and symptoms that can be clustered together ILAE- 3 groups related to age of onset and separate group for idiopathic
32
What are factors used to help identify specific epilepsy syndromes?
Age of onset of seizures Types of seizures Specific EEG patterns and imaging Associated co-morbidities (e.g learning difficulties) Aetiology (cause) of the epilepsy if known
33
What is status epilepticus?
A prolonged convulsive seizure lasting 5 mins or longer OR recurrent seizures one after the other without recovery in between or more than 3 in an hour
34
Which patients could status epilepticus occur in?
Patients that have existing epilepsy Patients that have never had seizures
35
What are the triggers of status epilepticus?
Head injury Metabolic disturbance (hypoglycaemia) Cerebrovascular event (stroke) Alcohol withdrawal
36
What is the different type of status epilepticus?
Convulsive status epilepticus Tonic-clonic seizures Medical emergency as it increases likelihood of long term damage and even death
37
What should occur if a patient has a seizure in the community?
Note time of seizure Provide first aid: -protect patient from injury -do not restrain them -if/when seizure stops then check airways and place in recovery position
38
What should occur if a patient has a seizure lasting longer than 5 mins in the community?
Airways, respiratory and cardiac function must be secured Buccal midazolam (first line) or rectal diazepam This should only be administered by a trained personnel or specified individually agreed protocol draw up by specialist and family members
39
What should occur if a patient has a seizure in the hospital from 0-5 mins?
The seizure is timed from onset Establish IV access Airways must be secured and regular monitoring of cardiac and respiratory function set up Give high conc oxygen Give high potency thiamine (if suggestion of alcohol abuse) e.g pabrinex Give glucose if patient is hypoglycaemic
40
What should occur if a patient has a seizure in the hospital from 5-20 mins?
Get a bit more info about the patient- if pre-hospital benzo given Start setting up other investigations to help manage e.g chest x-ray, CT scan Give IV lorazepam (0.1mg/kg, max 4mg) or IV diazepam if lorazepam not available, alternative to this is buccal midazolam if no IV access, max of 2 doses to be given including pre-hospital dose
41
What should occur if a patient has a seizure in the hospital from 20-40 mins?
Alert anaesthetist and ICU- if pt isn't responding to treatment more intervention and care is needed Give 2nd line IV anti epileptic drug (AED)- this will depend on hospital protocols in place (in NICE guidance they mention use of phenytoin, fosphenytoin sodium and phenobarbital, however newer AEDs such as SV/ levetiracetam can be used)
42
What should occur if a patient has a seizure in the hospital from 40-60 mins?
Transfer to ICU and general anaesthesia would be administered: -propofol -midzolam -thiopental sodium EEG monitoring needs to be set up when giving the anaesthetic Anaesthetic continued for 12-24 hrs after last clinical/ electrographic seizure
43
What is the aim when treating patients with epilepsy?
Aim for monotherpay Decrease likelihood of interactions and SEs Usually doses are started low and then gradually titrated up until control is achieved
44
What should occur if a monotherpy of a first anti-epileptic drugs fails?
Treatment should be switched to another: -this is done by adding the 2nd and titrating up, while 1st is titrated down If the second AED fails, then combo therapy is considered: -only considered when monotherapy has been tried and not resulted in seizure freedom
45
What is the therapeutic drug monitoring of anti-epileptic drugs?
Regular blood tests are not generally recommended and should only be undertaken if clinically needed and recommended by the specialist
46
What would be the main reasons a blood test is recommended for therapeutic monitoring of anti-epileptic drugs?
To identify non-adherence Investigate suspected toxicity Adjustment of phenytoin doses Managing interactions with other meds For specific clinal conditions e.g organ failure, pregnancy
47
What other the major points to be aware of with AEDs?
Suicidal behaviour- seek medical advice immediately Anti-epileptic hypersensitivity syndrome- fatal- occur within 1-8 weeks of exposure Vit D supplementation- if immobile/ low sun exposure
48
Name different types of AEDs:
Sodium valproate Carbamazepine Ethosuximide Lamotrigine Levetiracetam Phenobarbital Phenytoin Many others
49
What is the safety update in sodium valproate?
Risk if birth defects and developmental disorders In women who take SV while pregnant: -1 in 9 babies will be at risk of birth defect (spina bifida, spinal and skull and organ malformation) -4 in 10 will be at risk of developmental disorder (late to learn to talk/walk/learn)
50
What is the guidance for prescribing sodium valproate in accordance to the MRHA safety alert?
All products containing SV or valproic acid should not be started and prescribed to patients under 55 years old (male and female) unless 2 specialists independently consider and document that other treatments are ineffective or not tolerated or unless there is compelling reasons that reproductive risks do not apply Girls and women need to have a pregnancy prevention programme
51
What should occur if patients are already prescribed sodium valproate?
They should be advised not to stop taking it unless they are advised by the specialist It has been advised that their treatment is: -reviewed with an annual risk acknowledgment form completed and -if the treatment is to continue, a second opinion signature is required -this process is also to be initiated for men as well as studies show it can affect male fertility
52
What is a pregnancy prevention programme?
Exclusion of pregnancy Risk of acknowledgment form- also signed by patient and thoroughly counselled Highly effective contraception
53
What is the primary indication of sodium valproate?
1st line- generalised tonic- clonic seizures, myoclonic, tonic or atonic seizures if pt not of child bearing age or on PPP Can be used as 2nd line for absence (focal) seizures if other AED not suitable/ tolerated Potential 1st line agent for Dravet's syndrome, Lennox-Gastaut syndrome Also add on therapy
54
What is the age of a child who is not considered child bearing age?
Girls under 10
55
What are the other indications of sodium valproate?
Migraine prophylaxis (unlicensed) Mania bipolar disorder (either as SV or as a semi-sodium valproate)
56
What are the SEs of sodium valproate?
Nausea, weight gain (monitor as factor for polycystic ovary syndrome) Transient elevation of LFTs, blood dyscrasias (e.g anaemia) Alopecia (hair loss) Liver toxicity Pancreatitis (very rare)
57
What are the notable pharmacokinetics of sodium valproate?
Crossed in through the placenta t1/2 ranges between 8-20 hours (usually shorter in children) Metabolised through the liver via glucoronidation Enzyme inhibitor of a few CYP enzymes (450,2C9)
58
What are the monitoring requirements for sodium valproate?
LFTs- before starting and within 6 months of starting FBC- before starting Monitoring blood dyscrasia Liver disorders-jaundice, non-specific symptoms e.g lethargy, drowsiness, loss of strength, N&V Pancreatitis (N&V, abdominal pain)
59
What is the primary indication of carbamazepine?
2nd line for focal seizures, other types of epilepsy that include benign epilepsy with centrotemporal spikes Can be considered in last line generalised tonic-clonic seizures (but be aware it can exacerbate myoclonic and absence seizures if they are present it is not suitable) Add on in focal seizures
60
What are the other indications of carbamazepine?
Prophylaxis in bipolar disorder unresponsive to lithium Trigeminal neuralgia (nerve pain in the face) Adjunct to acute alcohol withdrawal (unlicensed) Diabetic neuropathy (unlicensed)
61
What are the adverse SEs of carbamazepine?
Drowsiness, dry mouth, nausea, vision disorders (all can be related to dose so can limit dose increase) Blood disorders (leucopenia, eosinophilia, thrombocytopenia) Hyponatraemia Skin disorders
62
What are the notable pharmacokinetics of carbamazepine?
Enzyme inducer, induces multiple CYP enzymes in liver Multiple formulations (IR tabs, MR, liquid), different preps are not bio equivalent It is metabolised in liver and clearance can be affected by other drugs causing enzyme induction/ inhibition AND also induction of its own metabolism thus altering t1/2 of the drug after continued admin Interacts with other AEDs
63
What are the monitoring requirements for carbamazepine?
Pre-treatment screening in pts of Han Chinese or Thai origin for the allele HLA-B*1502 allele- increased risk of Steven-johnson syndrome (severe skin reaction) with this allele Plasma conc for optimum response 4-12mg after 1-2 weeks Manufacturer recommends blood counts, liver and renal function Monitor for any dyscrasia, liver or skin disorders
64
What are the other AEDs that relate to carbamazepine?
Oxcarbazepine Eslicarbazepine
65
Describe oxcarbazepine:
Analogue of carbamazepine (pro-drug)- converted in liver Weak enzyme inducer of CYP enzymes (3A4 and 3A5) Enzyme inhibitor or CYP2C19 Pts have hypersensitivity to carbamazepine have a 25-30% chance of experiencing similar reaction to this Has more linear pharmacokinetics- no self induction of metabolism so more preferable
66
Describe eslicarbazepine:
Like that of oxcarbazepine- weak inhibitor or inducer of certain CYP Doesn't affect its own metabolism/ clearance Long t1/2 so OD dosing Risk of hypersensitivity Similar SEs to oxcarbemazepine but can also prolong the PR interval
67
What is the primary indication of ethosuximide?
1st line and adjunctive for absence seizures, including in childhood 3rd line for epilepsy with myoclonic- atonic seizures (Doose syndrome) Also licensed for myoclonic seizures
68
What are the other indications for ethosuximide?
No other indications
69
What are the adverse SEs for ethosuximide?
GI discomfort (N&V, diarrhoea, constipation) Anxiety Sleep disturbances Behavioural disorders Ataxia (unco-ordinated movements and balance) Drowsiness Blood disorders Rash (Steven-Johnson syndrome)
70
What are the notable pharmacokinetics for ethosuximide?
Absorbed well orally, metabolised in the liver Available in soft capsule or syrup form Generally no notable interactions with AEDs
71
What are the monitoring requirements for ethouximide?
Monitor for any blood dyscrasias Should be taught to recognise signs e.g bruising, bleeding, fever, rash Monitor for suicidal behaviours
72
What is the primary indication for lamotrigine?
1st line and adjunctive for focal, generalised tonic-clonic seizures, absence seizures (if ethosuximide or SV not suitable/tolerated), tonic or atonic seizures, idiopathic generalised epilepsy 2nd or 3rd line for myoclonic seizures (caution as can exacerbate)
73
What are the other indications for lamotrigine?
Bipolar disorder (monotherapy or as adjunctive) Neuropathic pain
74
What are the adverse SEs of lamotrigine?
Dizziness, drowsiness, headache, dry mouth, diplopia, rash (more common when given with other AEDs or in too rapid dose titration), hypersensitivity syndrome, suicidal ideation, blood disorders
75
What are the notable pharmacokinetics of lamotrigine?
When given with drugs that are hepatic enzyme inducers or inhibitors, the t1/2 is altered, dosage of the drug needs to be adjusted for this Does induce its own metabolism but doesn't affect other AEDs
76
What are the monitoring requirements for lamotrigine?
Counsel to patients: Skin reactions- immediately to doctor Bone marrow failure- anaemia, bruising, infection
77
What is the primary indication for levetiracetam?
1st line for generalised tonic-clonic seizures, focal seizures, myotonic seizures, idiopathic generalised seizures 2nd line for absence seizures, myoclonic, idiopathic generalised seizures and other epilepsy syndromes Adjunctive in focal, generalised tonic-clonic and myoclonic seizures
78
What are the other indications of levetiracetam?
No other indications
79
What are the adverse SEs of levetiracetam?
Drowsiness, dizziness, anxiety, GI discomfort, asthenia (lack of energy), insomnia, behavioural abnormalities (aggression/irritability), rash Uncommon/rare- suicidal behaviours, thrombocytopenia, leukopenia
80
What are the notable pharmacokinetics of levetiracetam?
Oral bioavailability is almost 100% with linear pharmacokinetic profile, allowing plasma levels to be more predictable therefore plasma monitoring not needed It is not extensively metabolised in the body and a large proportion is excreted through the kidneys unchanged Some of the drug is metabolised though hydrolysis and doesn't require CYP450 hepatic isoforms
81
What are the monitoring requirements for levetiracetam?
None except general counselling of AEDs
82
What are the primary indications for phenobarbital?
No 1st line indications NICE recommends its use as an adjunctive 2nd line option in generalised tonic-clonic seizures 3rd line add on in focal and myoclonic seizures It is licensed for all epilepsy types except typical absence seizures, also in use in status epilepticus as IV
83
What are the other indications of phenobarbital?
No other indications
84
What are the adverse SEs of phenobarbital?
AED hypersensitivity syndrome (Steven-Johnson syndrome), bone fractures and bone disorders, blood disorders, folate deficiency, drowsiness, suicidal behaviour, hepatic disorders
85
What are the notable pharmacokinetics of phenobarbital?
Metabolism of drug varies in neonates and children Partly metabolised in liver, some is excreted unchanged from kidneys Crosses the placenta barrier and is present in breast milk Enzyme inducer of Cyp450 (potent)
86
What are the monitoring requirements for phenobarbital?
Optimum plasma conc levels are 15-40mg/L however due to tolerance occurring with phenobarbital measuring these levels may not be as useful as other AEDs Monitor for suicidal behaviours Skin reactions-report signs and symptoms of rash or hypersensitivity syndrome
87
What is the primary indication of phenytoin?
No 1st line indications Adjunctive 3rd line in focal seizures Use in tonic-clonic and focal seizures or absence seizures however NICE states that if myoclonic or absence seizures are present then phenytoin should not be used The BNF also states use in the prevention of seizures during or following neurosurgery or severe head injury
88
What are the other indications of phenytoin?
Trigeminal neuralgia (unlicensed and under specialist)
89
What are the adverse SEs of phenytoin?
Drowsiness, confusion, hirsutism, gingival hyperplasia, cerebellar dysfunction, bone and bone marrow disorders, (can affect hematopoietic system formation of different blood types of cells resulting in megaloplastic anaemia, granulocytopenia) Symptoms of phenytoin toxicity: -nystagmus (rapid eye movement) -diplopia -slurred speech -ataxia -confusion -hyperglycameia (inhibits glucose metabolism, stop insulin release)
90
What are the notable pharmacokinetics of phenytoin?
Highly protein bound (around 90%) Clearance of the drugs is through the liver but follows non-linear kinetics (saturation of the clearance pathways occurs at therapeutic doses) which can have knock on effects of half life Available in various formulations- IV, caps, tabs, liquid NOT all bioequivalent Phenytoin sodium ≠ phenytoin base, 100mg PS=92mg PB Enzyme inducer of CYP450
91
What are the monitoring requirements for phenytoin?
Due to its pharmacokinetic profile monitoring may be needed in certain patient groups/situations where protein binding may be decreased (pre, elderly, when admin with other meds) Free plasma phenytoin may be more appropriate Monitor for any blood dyscrasia or skin disorders With IV use monitor ECG and BP Pre treatment- HBLA*B1502- Steven-Johnson
92
Name other AEDs:
Clobazam Lacosamide Gabapentin Pregabalin Rufinamide Vigabatrine Tiagabine Topiramate Zonisamide Perampenal Brivaracetam
93
What are the different categorises AEDs are put into?
Category 1,2,3
94
What do category 1 AEDs mean?
Patients should be maintained on a specific manufacturer brand Don't switch
95
Name examples of category 1 AEDs:
Carbamazepine Phenobarbital Phenytoin Primidone
96
What do category 2 AEDs mean?
The need for continued supply of a particular manufacturers product should be based on clinical judgement and consultation with pt/carer taking into account clinical and non clinical factors
97
Name examples of category 2 AEDs:
Clobazam Clonazepam Zonisamide Eslicarbazepine Lamotrigine Perampanel Oxcarbazepine Rufinamide Topiramate SV
98
What do category 3 AEDs mean?
Usually unnecessary for pts to be maintained on specific manufactures brand as therapeutic equivalent is assured Non clinical factors should be considered
99
What are clinical factors relating to changing AEDs?
Relating to seizure freq Treatment history Complications of having a breakthrough seizure e.g if driving as a job, could lose job
100
What are the non-clinical factors relating to changing AEDs?
Alternative medication could have a negative effect on pt/carer leading to anxiety, confusion, admin errors or changing adherence
101
Describe the ketogenic diet in relation to treating epilepsy:
Non-pharmacological High fat, low protein and carb diet and is mainly used with patients with difficult to treat epilepsy (intractable epilepsy) NICE recommends it should only be used in 3º care epilepsy specialists
102
How does the ketogenic diet work in relation to treating epilepsy?
The diet mimics the state of starvation for the brain, forcing the body to break down fat instead of carbs to produce energy Ketones are produced so have anti convulsive properties
103
Name the 3 different types of ketogenic diets:
Classical ketogenic diet Modified ketogenic diet Medium chain triglyceride diet
104
What type of drugs can exacerbate epileptic seizures?
Prescription and illicit- including alcohol Ways in which drugs can trigger seizures include: -induction or inhibition of hepatic enzymes- alter pharmacokinetics (plasma conc affected) -some AEDs can themselves worsen and/or precipitate seizures -2º effects of other drugs used for other reasons e.g decrease in Na+ or serotonin syndrome -renal/hepatic impairment -co admin of other drug cautioned e.g theophylline
105
Describe the withdrawal procedure for epilepsy patients on AEDs:
Aim for treatment to be discontinued in patients that have been seizure free for at least 2 years The AED would be slowly withdrawn over 3 months, can be longer Pts who are on barbiturates/ benzodiazepines, withdrawal must be much slower (6 months) due to withdrawal symptoms and potential seizure recurrence If patients are on multiple AEDs one drug must be withdrawn at a time
106
What factors should be taken into account by the specialist when deciding whether to withdraw AEDs?
Risk and benefits Risk of seizure recurrent Risk of SUDEP Risk of job Multi factorial risk factors: -epilepsy surgery -epilepsy type/syndrome -cause of epilepsy -abnormal MRI imaging
107
Which 2 categories can AEDs be divided into?
Enzyme inducers Non enzyme inducers
108
Name the enzyme inducing AEDs:
Carbamazepine Eslicarbazepine Oxcarbazepine Perempanel (doses over 12mg daily) Phenobarbital Phenytoin Primidone Rufinamide Topiramate (doses over 200mg)
109
Name the non enzyme inducing AEDs:
Acetazolamide Clobazam Clonazepam Ethosuximide Gabapentin Lacosamide Lamotrigine (COC can affect metabolism of this though) Levetiracetam Perampanel (doses below 12mg) Pregabalin SV Tiagabine Topiramate (doses below 200mg) Vigabatrin Zonisamide
110
What are the contraceptives which are not effective in enzyme inducing AEDs?
Oral POP Progesterone only implant COC with less than 50mcg of ethinyestradiol
111
What should occur even after an enzyme inducing AED is withdrawn?
The enzyme induction persists for 4 weeks after and therefore contraception methods must be continued during this time
112
What is the guidance for emergency contraception with enzyme inducing AEDs?
1st- copper IUD (most effective) 2nd- Levonorgestrel 1.5 mg tabs- double dose should be taken to provide cover if copper IUD not suitable/ acceptable 3rd- ulipristal acetate 30mg tablet- effectiveness unknown
113
What are the contraceptives used in non-enzyme inducing AEDs?
Normal contraceptive methods can be used Except for lamotrigine
114
Describe what measures need to be taken with contraception and lamotrigine?
COC can decrease the efficacy of lamotrigine (including glucornidation, decreases serum lamotrigine levels): -increased risk of seizures 21 days -increased risk of toxicity 7 day free period so continuous COC would be better A POC desogestrel is also thought to potentially increase the exposure of lamotrigine Additional barrier advised
115
What contraceptions are not thought to be affected by lamotrigine?
Levonorgestrel IUD Copper IUD Injection Still need to monitor lamotrigine levels
116
What is the pre-conception advice for women who are planning to become pregnant with AEDs?
NICE recommend monitoring anti epileptic drug levels who are planning to become pregnant and are considered at risk of their seizures worsening- obtain baseline conc
117
What are the medications that should be monitored pre/during conception of AEDs?
Phenytoin Oxcarbamazepine Phenobarbital Carbamazepine Lamotrigine Levetriacetam
118
What are the safest AEDs to use during pregnancy and why?
Lamotrigine and levetiracetam They don't increase the risk of birth abnormalities compared to the general population
119
What are the AEDs that can affect babies during pregnancy and why?
Carbamazepine, phenobarbital, phenytoin or topiramate use during pregnancy increases the risk of physical birth abnormalities compared to the general population Phenobarbital, topiramate or zonisamide during pregnancy increases the risk of baby born smaller than expected compared to general pop
120
What are the AEDs that can affect babies after pregnancy and why?
Phenytoin or phenobarbital taking during pregnancy can increase the risk of child having difficulty with learning and thinking ability (neurodevelopmental adverse effects)
121
List the AEDs and the physical number of birth defects they can have on babies:
General population 2-3/100 Carbamazepine 4-5/100 Phenobarbital 6-7/100 Phenytoin 6/100 Topiramate 4-5/ 100 Valproate 10/100
122
What supplement does a pregnant women taking AED need to take and why?
5mg fold acid at least 1st trimester-often longer To help prevent neural tube defects
123
What are the factors that should occur when a patient with epilepsy is pregnant?
Notify the UK Epilepsy and Pregnancy register- pt choice Care of women with epilepsy when pregnant should be shared with the epilepsy specialist, 1º care team and obstetrician/midwife Some patients need more frequent review based on certain factors Detailed ultrasound at 18-20 weeks to scan for structural abnormality
124
Which patient factors would mean a pregnant patient with epilepsy would need to be reviewed more frequently?
Sleep deprivation Patient adherence / compliance Seizure type/frequency Learning disabilities Less than 16 years old Active epilepsy (last 12 months) Bilateral tonic-clonic seizures Modifiable risk factors for SUDP
125
What is the risk of seizures like in pregnancy for epileptic women?
Unlikely to experience an increase in seizure frequency or during first few months after birth Increase risk in patients that have generalised tonic-clonic seizures (foetus may be at higher risk of harm)
126
What is the risk of seizures like during labour for epileptic women?
Risk of seizure low but it is recommend to give birth in hospital Patients would be kept under close observation in hospital In an open bay and not a closed room alone as risk of SUDP
127
What should be the procedure after birth for babies and mothers who have epilepsy?
Babies born to mothers who are on enzyme inducing AEDs are given 1mg vitamin K parentally at delivery Patients are encouraged to breastfeed as it is generally safe- but always consult SPC
128
What are the safety precautions advised for epileptic mothers and babies when back at home after pregnancy to decrease harm if the mother has a seizure?
Bathing- shower if washing alone, bath only if with someone Feeding- sitting on the floor with mothers back against the wall, using cushions either side to decrease risk of child falling on hard floor Changing nappies- change on the floor Going outside- length of cord attached to pram to stop pram from rolling away
129
Describe the correlation with epilepsy and bone health:
Related to long term use of AEDs increase the likelihood of bone loss, decreased bone density, risk of osteoporosis and fractures (at least in part as a result of fractures) Thought to be due to metabolism of VitD by CYP450 enzymes Risk of bone health increases if on multiple AEDs or for long periods of time
130
What are the AEDs which can decrease bone health?
Enzyme inducers: carbamazepine, phenytoin, primidone Non-enzyme inducers: SV
131
What is the NICE guidance for bone health with AEDs?
Monitor VitD levels of patients on these AEDs and supplementation to those at risk Other tools such as DEXA/FRAX Counselling on bone health important: -healthy diet, healthy sun exposure, exercise, smoking and alcohol cessation
132
What are the rules when a patient has epilepsy and drives?
The patient must inform the DVLA if they have an epileptic seizure or blackout and stop driving immediately -pts who fail to inform DVLA could face a fine of £1000 and be prosecuted -informing DVLA can be done online or by filling in an FEP1 form Tougher rules for bus, coach, lorry driving licenses