Neuro Flashcards
What are the major symptoms of Parkinson’s disease?
TRAP:
Tremor
Rigidity
Akinesia/bradykinesia
Postural instability
Drugs that can worsen Parkinson’s disease
Phenothiazines (prochlorperazine, etc.)
Butyrophenones (haloperidol, droperidol)
1st and 2nd gen antipsychotics
Metoclopramide
Which med is preferred for the treatment of PD-associated psychosis?
Quetiapine
Rapid withdrawal of levodopa or dopamine agonists can cause what condition?
Neuroleptic malignant syndrome
What is the active metabolite of levodopa?
Dopamine
Why is carbidopa given in combo with levodopa?
Prevents the peripheral metabolism of levodopa that would destroy most of the drug before it crosses the BBB
What drug is 1st line for the treatment of PD?
Carbidopa/levodopa (Sinemet)
Which PD drugs are used to reduce “off” periods and to limit dyskinesias?
COMT inhibtors and MAO-B inhibitors
What drug can be used in younger PD pts to treat tremor-predominant disease?
Centrally-acting anticholinergics (benztropine)
Amantadine is also an option
Key points for carbidopa/levodopa
Starting IR dose = 25/100 mg tid
CI w/ non-selective MAOi and narrow angle glaucoma
SE: Nausea, dizziness, orthostasis, dyskinesias, hallucinations, psychosis, unusual sexual urges, pripism
Can cause brown/black urine discoloration
must d/c if positive Coombs test
Response worsens with long-term use
Must taper if stopping
Examples of catechol-O-methyltransferase (COMT) inhibitors
Entacapone (Comtan)
Opicapone (Ongentys)
Tolcapone (Tasmar)
When can COMT inhibitors be used?
Must be used in combo with levodopa - increases the duration of action of levodopa (prevents peripheral conversion)
Examples of dopamine agonists
Pramipexole (Mirapex)
Ropinirole (Requip)
Key points for dopamine agonists
Warnings for somnolence, orthostasis, hallucinations, dyskinesias
Must be tapered if stopping
For patch, cannot use same site for 14 days after use (daily patch)
Cannot use patch with sulfite allergy
What drug can be used as a rescue drug for off-periods for PD?
Apomorphine
Must be started in medical office
Key points for amantadine
Blocks dopamine reuptake and increases dopamine release from presynaptic fibers
Warnings for somnolence and psychosis
SE: Dizziness, orthostatic hypotension, livedo reticularis (reddish skin mottling)
Examples of selective MAO-B inhibtors
Selegiline
Rasagiline
Safinamide
Key points for MAO-B inhibitors
CI w/ MAOi, SSRIs/SNRIs, linezolid, opioids, TCAs
Same food interactions as MAOi’s
Risk of serotonin syndrome and HTN
Selegiline can be activating - do not take at night
Key points for benztropine (Cogentin)
Has anticholinergic and antihistamine effects
SE: dry mouth, constipation, urinary retention, blurred vision. mydriasis, somnolence, confusion
Avoid in elderly pts
Drugs that can worsen dementia
Antiemetics (promethazine)
Antihistamines (benadryl, doxyalamine)
Antipsychotics (chlorpromazine, aripiprazole)
Barbituates (phenobarb)
BZDs
Anticholinergics
Skeletal muscle relaxants (baclofen)
CNS depressants
What test is used to diagnose dementia?
Mini-Mental State Exam (MMSE)
Score <24 = memory disorder
What supplements have shown possible benefit for Alzheimer’s dementia?
Vit E and ginkgo
Both increase bleed risk
What drug(s) are first line for the treatment of Alzheimer’s disease?
Acetylcholinesterase inhibitors (donepezil)
+/- memantine
What time of day should donepezil be taken at?
Bedtime (decreases nausea)
Can take in AM if causes insomnia
Examples of acetylcholinesterase inhibitors
Donepezil (Aricept)
Rivastigmine (Exelon)
Galantamine (Razadyne)
Key points for acetylcholinesterase inhibitors
Warnings for bradycardia and QT prolongation
SE: N/D
Rivastigmine patch = daily dosing, same site cannot be used for 14 days
Key points for memantine (Namenda)
Blocks NMDA receptors
SE: Dizziness, confusion, HA
Drugs that can lower the seizure threshold
Bupropion
Clozapine
Theophylline
Varenicline
Carbapenems (esp imipenem)
Lithium
Meperidine
Penicillin
Quinolones
Tramadol
Acyclovir/Valacyclovir
Focal vs generalized seizures
Focal = starts on one side of the brain
Generalized = starts on both sides of the brain
Define status epilepticus
Seizure that lasts 5 mins or more
Medical emergency
Initial management for status epilepticus
Benzodiazepine injection
- can also use diazepam rectal gel
What diet can benefit some patients with refractory seizures?
Ketogenic diet
Which drug is used for absence seizures?
Ethosuximide
Which neurotransmitter abnormalities can lead to seizures?
High glutamate
Low GABA
Which antiepileptic drugs are Na channel blockers?
Carbamazepine
Lamotrigine
Phenytoin/fosphenytoin
Topiramate
Oxcarbazepine
Key points for lamotrigine
Warnings for serious skin rxns
SE: alopecia (give Se and Zn), rash
Different colored starting dose boxes:
- red: normal dose
- blue: low dose, use if taking valproic acid/inhibitors
- green: high dose, use if taking inducers (phenytoin)
Key points for levetiracetam
IV:PO is 1:1
Warnings for psych rxns (psychotic symptoms), somnolence, fatigue
No significant drug interactions
Max 3g per day
Key points for topiramate
Warnings for metabolic acidosis, oligohidrosis, hyperthermia, nephrolithiasis, glaucoma, hyperammonemia, visual problems, fetal harm
SE: somnolence, memory/concentration/attention difficulty, weight loss, anorexia
Must monitor bicarb and intraocular pressure
Can decrease OC efficacy
Key points for valproic acid/divalproex
Therapeutic range = 50-100 mcg/mL
Warnings for hepatic failure, fetal harm, hyperammonemia, thrombocytopenia
SE: alopecia (give Se and Zn), weight gain
Serious rash can occur w/ valproic acid + lamotrigine
Key points for carbamazepine
Therapeutic range = 4-12 mcg/mL
Warnings for serious skin rxns, testing for HLA-B*1502 allele prior to starting, aplastic anemia, agranulocytosis, SIADH, fetal harm
CI w/ myelosuppression
Enzyme inducer and autoinducer (lowers own drug levels)
Many DDIs, decreases OC efficacy
Key points for lacosamide
Warnings for PR prolongation and arrhythmias
Max 400 mg per day
IV:PO is 1:1
Key points for oxcarbazepine
Warnings for severe skin reactions, test for HLA0B*1502 and hyponatremia
XR must take on empty stomach
Not an autoinducer
Can decrease OC efficacy
Phenobarbital key points
Therapeutic range = 20-40 mcg/mL (adult)
Warnings: habit forming, resp depression, fetal harm
SE: physiological dependence, tolerance, hangover effect
Can decrease OC efficacy, strong inducer
Which drug is a prodrug of phenobarbital?
Primidone
Key points for phenytoin and fosphenytoin
Total range = 10-20 mcg/mL
Free range = 1-2.5 mcg/mL
IV:PO = 1:1
Arrhythmias associated with fast drip rates
Warnings for extravasation (purple glove syndrome), avoid in HLA-B*1520 + pts, fetal harm
SE: nystagmus, ataxia, diplopia, gingival hyperplasia, hepatotoxicity, hair growth
Strong inducers, high protein binding
Can decrease OC efficacy
Requires a filter
IV requires BP, resp, and ECG monitoring
Enteral feeds decrease phenytoin absorption
What is the max administration rate for IV phenytoin?
50 mg/min
What is the max administration rate for IV fosphenytoin?
150 mg PE/min
What is the active metabolite of eslicarbazepine?
Oxcarbazepine
Main side effect for vigabatrin
Permanent vision loss (30% of pts)
What allergy has cross reactivity with zonisamide?
Sulfonamide allergy
When must the phenytoin correction calculation be used?
If albumin <3.5 and CrCl >10 mL/min
All antiepileptic drugs cause what SE?
CNS depression
Bone loss (must supplement VitD and Ca)
Warning for suicide risk
Antiepileptic drugs that are enzyme inducers
Carbamazepine
Oxcarbazepine
Phenytoin
Fosphenytoin
Phenobarbital
Primidone
Antiepileptic drug that is an enzyme inhibitor
Valproic acid
Which antiepileptic meds have higher risks when used in children?
Topiramate (hyperthermia)
Zonisamide (hyperthermia)
Lamotrigine (rash)
