Seizure Treatment Algorithm Flashcards
Approach to a patient with 1st seizure
What are the questions to consider?
- Was it a seizure?
- Was it the first seizure?
- Was it a provoked seizure? If not, what is the likely etiology?
- Does the pt need ASM?
Considerations to starting ASM in pt with 1st seizure
What are the questions to consider?
- What is the risk of seizure recurrence?
- What are the patient factors?
- Which ASM to start?
Risk of seizure recurrence after 1st seizure, is higher in:
- Epileptiform abnormalities on EEG
- Prior brain insult (e.g., stroke, brain trauma/injury)
- Structural abnormality in brain imaging (MRI)
- Nocturnal seizure
Risk is higher in first 2 years after 1st seizure
After 2 unprovoked seizures, risk of recurrence is higher
Are there benefits to starting ASM after the 1st seizure?
What do the findings imply?
Benefits:
- Reduced risk of second seizure
However,
- No effect on long-term prognosis
- No evidence of higher risk of death, injuries, or status epilepticus in patients who defer treatment
Implication:
- Not much benefit to starting if pt does not have high risk of seizure recurrence after 1st seizure
- Therefore, important to discuss with pt, look at considerations + key determinants
What are the key determinants to the following considerations when deciding when to start treatment?
- Recurrence risk
- Potential seizure morbidity
- Risk of treatment
- Personal circumstances
no need to memorise, but need to be able to consider
Recurrence risk
- EEG findings, MRI findings, epilepsy syndrome, cause (structural insult), nocturnal seizures
Potential seizure morbidity
- Seizure type
Risk of treatment
- Tolerability, side effects
Personal circumstances
- Work, need for driver license, desire to bear children
What are the treatment goals in epilepsy?
- Absence of epileptic seizures
- Absence of ASM-related SEs
- Attainment of optimal QoL
About 2/3 of pt able to achieve seizure-freedom
Choice of medication
What are the key determinants to the following considerations when deciding which ASM to start?
- Efficacy and effectiveness
- Tolerability
- Pharmacokinetics
- Personal preferences
- Nation-specific factors
Efficacy and effectiveness
- seizure type
- epilepsy syndrome
Tolerability
- Drug profile effects on comorbidity, other meds, tolerability in special populations
Pharmacokinetics
- DDI
- Protein binding
- Hormonal effects
- Liver/Renal impairment
Personal preferences
- Formulation
- Dosing frequency
Nation-specific factors
- Guidelines
- Availability
- Cost
- Insurance coverage
Compare and contrast choice of Carbamazepine VS Lamotrigine VS Levetiracetam for focal onset epilepsy
Carbamazepine
- Potent inducer, check for DDIs
Lamotrigine
- Requires slow titration due to risk of SJS/TEN, is there urgency to increase dose rapidly?
Levetiracetam
- No CYP interactions, 1st order kinetic, <10% protein bound
- BUT a/w psychiatric and behavioural SEs (may not be good choice esp if pt has existing psychiatric problems)
When to start treatment?
- High recurrence risk after 1st seizure
- After second seizure
- Once diagnosis of epilepsy confirmed
- After first unprovoked seizure if any of the following apply:
- Examination identifies signs of neurological deficit
- EEG shows unequivocal epileptic activity
- Brain imaging shows structural abnormality
- After discussion of risk of further seizures with person/family
Two key factors to evaluate for epilepsy treatment
- Efficacy (seizure freedom)
- Tolerability (side effects)
- If not efficacious => either increase dose (if tolerable side effects) or decrease dose/switch/add second age (if intolerable side effects)
- If efficacious => continue treatment (if tolerable side effects) or decrease dose (if intolerable side effects)
[Stopping treatment]
- When to consider discontinuation
Drug discontinuation may be considered after minimum 2y without a seizure (seizure free >2y)
- but if pt has incr risk of seizure recurrence, advisable to wait beyond 2y
- balance risk of continuation (chronic toxicity, teratogenicity) with the implications of relapse (injury, SUDEP, employment)
[Stopping treatment]
Decision to discontinue should be documented:
- Reasons for discontinuation
- Taper schedule
- Plans for monitoring patients during and after ASM taper
- Patients motivation for, attitude towards and understanding of potential risks and benefits of ASM discontinuation compared with continuing ASM therapy
[Stopping treatment]
Taper schedule should be ______ taking into account what factors?
Taper schedule should be individualized, taking into account factors such as:
- Risk factors for seizure recurrence
- Seizure frequency
- Number of medications
[Stopping treatment]
Based on NICE guideline:
- Medications should be reduced gradually over ______, what are the exceptions?
- If pt was on multiple ASM…
- Medications should be reduced gradually over at least 3 months
- Benzodiazepine and Barbiturates / Phenobarbital over longer period to reduce risk of drug-related withdrawal symptoms
- If pt was on multiple ASM, discontinue one at a time
[Stopping treatment]
Based on NICE guideline:
If seizure recurs during discontinuation, what should be done?
Reverse the last dose reduction, seek guidance from epilepsy specialist
