Neurology Flashcards
Glaucoma drugs that decrease aqueous humor synthesis
alpha-agonists (epinephrine, brimonidine) - causes mydriasis so do not use in closed-angle glaucoma; also causes visual changes
beta-blockers (timoloil, betaxolol, carteolol) - no pupillary or vision changes
carbonic anydrase inhibitors (acetazolamide) - no pupillary or vision changes
Glaucoma drugs that increase aqueous humor outflow
direct cholinomimetics (pilocaropine, carbachol)
indirect cholinomimetics (physostigmine, echothiophate) - contract ciliary muscles and open trabecular meshwork; cause miosis; use pilocaropine in emergencies
prostaglandins (latanoprost) - brown color of iris
Ethusuximide
First-line treatment of absence seizures.
Blocks thalamic T-type Ca channels.
Toxicities: GI distress, pruiritis, and Stevens-Johnson syndrome
Treatment of absence seizures
Ethusuximide (first line), valproic acid, lamotrigine
Treatment of status epilepticus
Benzos (acute tx) and Phenytoin (prophylactic tx)
Phenytoin
First-line treatment of tonic-clonic seizures (along with carbamazepine and valproic acid). Also used as prophylactic tx for status epilepticus.
Increases Na channel inactivation.
Toxicity: Nystagmus, diplopia, ataxia, gingival hyperplasia, teratogenesis, SLE-like syndrome, induction of P-450, Stevens-Johnson syndrome, pseudo-lymphoma
Carbamazepine
First-line treatment of simple, complex, and tonic-clonic seizures. Also functions as mood-stabilizer
Increases Na channel inactivation.
Toxicity: Diplopia, ataxia, bone marrow suppression, SIADH, teratogenesis, inducation of P-450, Stevens-Johnson syndrome
Valproic acid
First-line treatment of tonic-clonic seizures (along with carbamazepine and phenytoin). Also used for absence seizures, myoclonic seizures, and bipolar disorder (functions as mood stabilizer)
Increases Na channel inactivation and increases GABA concentration by inhibition GABA transaminase.
Toxicity: Rare but fatal hepatotoxicity; spina bifida, weight gain
Gabapentin
Treats simple, complex, and tonic-clonic seizures. Also used for peripheral neuropathy, postherapeutic neuralgia, migraine prophylaxis, and bipolar disorder.
Inhibits high-voltage-activated Ca channels; GABA analog.
Toxicity: sedation, ataxia
Topriamate
Treats simple, complex, and tonic-clonic seizures. Also used for migraine prophylaxis.
Blocks Na channels, increases GABA action.
Toxicity: sedation, kidney stones, weight loss
Lamotrigine
Treats simple, complex, tonic-clonic, and absence seizures. Also treats depressive phase of Bipolar disorder
Blocks voltage-gated Na channels.
Toxicity: Stevens-Johnson syndrome if titrated quickly
Stevens-Johnson syndrome
Prodrome of malaise and fever followed by rapid onset of erythematous macules that progress to toxic epidermal necrolysis
Order of nerve blockade of local anesthetics
Small myelinated fibers > small unmyelinated fibers > large myelinated fibers > large unmyelinated fibers.
Order of Loss: pain > temperature > touch > pressure
Dantrolene
Treats malignant hyperthermia and neuroleptic malignant syndrome
Prevents the release of Ca from the SR of skeletal muscle
Bromocriptine, Pergolide (ergot),
Pramipexole, Ropinirole (non-ergot)
Dopamine agonists used to treat Parkinson disease.
Ergots (bromocriptine) are preferred
L-dopa/carbidopa
Increase dopamine levels in the brain to treat Parkinson disease.
Unlike dopamine, L-dopa can cross the BBB and is converted to dopamine by dopa decarboxylase in the CNS.
Carbidopa (peripheral decarboxylase inhibitor) increases the bioavailability of L-dopa in the brain
Amantadine
Increase dopamine levels in the brain to treat Parkinson disease. Also used to treat influenza A and rubella.
Toxicity is ataxia.
Selegiline
Prevents dopamine breakdown to treat Parkinson disease.
Inhibits MAO-B, which preferentially metabolizes dopamine over norepinephrine and 5-HT.
Used as an adjunctive treatment to L-dopa
Entacapone, tolcapone
Prevents dopamine breakdown to treat Parkinson disease. Inhibits COMT.
Benztropine
Antimuscarinic that treats tremor and rigidity in Parkinson disease. Little effect on bradykinesia.
Memantine
NMDA receptor antagonist that treats Alzheimer disease.
Toxicity: dizziness, confusion, hallucinations
Donepezil, galantamine, rivastigmine
AChE inhbitors that treat Alzheimer disease.
Treatment of Huntington disease
Tetrabenazine and reserpine - inhibit vesicular monoamine transporter (VMAT) to limit dopamine packaging and release
Haloperidol - dopamine receptor antagonist
Sumatriptan
Treatment of acute migraines and cluster headaches. 5-HT1b agonist that inhibits trigeminal nerve activation, prevents vasoactive peptide release, and induces vasoconstriction or cranial and basilar arteries.
Contraindicated with CAD or Prinzmetal angina due to risk of coronary vasospasm.
Extra-CNS effects of inhaled anesthetics
Myocardial depression
Respiratory depression (except nitrous oxide)
Depression of mucociliary clearance (may predispose to postop atelectasis). Halothane and sevoflurane have bronchodilation properties (use in patients with asthma)
Increase cerebral blood flow and ICP (due to decreased vascular resistance in the brain)
Decrease GFR
Decrease hepatic blood flow
Primidone
Anti-epileptic, metabolized to phenobarbitol (causes lethargy)
