Neurology Flashcards
When making a diagnosis of epilepsy what is the most useful component of assessment?
History of symptoms
Pallor
UI
Tongue biting
Postictal confusion, drowsiness, paresis or speech disturbance
What is the utility of an EEG in making diagnosis of epilepsy?
Interictal EEG may be limited utility on older adult, low Sn and Sp
Non specific EEG abnormalities seen in 12-38% older adults without seizures
Normal EEG doesn’t rule out epilepsy, seen in about 1/3 patients
Can assess for focal vs. generalized which can guide treatment options
Identify ongoing epileptiformn activity which is risk for recurrence
What is the most likely type of seizure in older adults?
Focal onset
With or without evolution to bilateral tonic-clonic seizures
What would lead you to treat patient for epilepsy?
- 2 unprovoked seizures
- EEG findings of epileptiform abnormalities
- CT head no acute stroke or bleed
4 things to be cautious of when starting anti epileptic
- Drug drug interactions
- Risk of further cognitive impairment
- Predispose to arrhythmias
- Risk of osteoporosis
- Renal and hepatic function
What are the etiologies of epilepsy in the elderly?
- Cerebrovascular - post infarct, SAH or ICH
- Neurodegenerative disease
- Brain tumor
- TBI
- Metabolic/infectious
50% unknown
What are 4 things to consider when prescribing anti epileptics?
- Efficacy
- Potential adverse effects
- Drug drug interactions
- Economic/practical factors
What are the recommendations for which anti epileptic to use?
Lamotrigine and gabapentin seem to be first line choices
Other: carbamazepine, topiramate, valproate
What are common side effects of lamotrigine?
Rash
Helps with depression
What are common side effects with gabapentin?
Weight gain
What are common side effects with carbamazepine?
GABA agonist
Confusion/drowsiness
HypoNa
Cardiac conduction
Weight gain
Rash
What 3 anti epileptics cause cognitive impairment?
Phenytoin
Topiramate
Zonisamide
What pharmacodynamic changes occur with aging that affects AEDs?
Decreased number and sensitivity of receptors = hard to keep stable levels
What blood work would you send for somebody presenting with seizures?
CBC
Lytes/extended lytes
Cr
Lactate/CK
Blood glucose/A1c
Tox screen
What anti depressant would you not prescribe in patient with seizures?
Bupropion - lowers seizure threshold
How can malnutrition affect pharmacokinetics of AEDs?
Most bind to albumin and become inactive
If you have malnutrition = lower albumin = more free and active drug
Why is phenytoin not recommended as an AED?
Drug drug interactions
Narrow therapeutic window
Cognitive impairment
Cardiac conduction abnormalities
Diplopia
Nystagmus
What should you know before deciding to take somebody off of phenytoin?
Was seizure provoked?
If provoking factor modifiable?
Hx of other seizures?
What were EEG results?
MRI results?
Patient preference
Experiencing AEs
What medications can decrease seizure threshold?
Moderate risk
Methotrexate
Olanzapine/clozapine
Intermediate
TCAs, bupropion
Flagyl
Low risk
Quetiapine, risperidone
SSRIs
MAOis
Quinolones
Beta blockers
Donepezil
What DOAC interacts with phenytoin?
Phenytoin decreases rivaroxaban
Since it is a Pgp inducer and CYP3A4 inducer, both of which metabolize rivaroxaban
