Neuro Drugs Flashcards
(48 cards)
1
Q
Epinephrine, Brimonidine
A
alpha 2 agonists
- decreased aqueous humor synthesis
- SE (epi): mydriasis, do not used in closed-angle glaumcoma
- SE (brimonidine): blurry vision, ocular hyperemia, foreign body sensation, ocular allergic reactions, ocular pruritis
2
Q
timolol, betaxolol, carteolol
A
beta blockers
- decreased aqueous humor synthesis
- no pupillary or vision changes
3
Q
acetazolamide
A
carbonic anhydrase inhibitor
- decreased aqueous humor synthesis, no pupillary or vision changes
- SE: somnolence, paresthesias, urinary alkalosis
4
Q
pilocarpine, carbachol
A
- direct cholinomimetics
- increase outflow of aqueous humor via contraction of the ciliary muscle and opening of trabecular meshwork
- SE: miosis and cyclospasm (contraction of ciliary muscle)
5
Q
physostigmine, echothiophate
A
indirect cholinomimetics
- use pilocarpine in emergencies, very effective at opening meshwork into canal of Schlemm
- SE: miosis and cyclospasm (contraction of ciliary muscle)
6
Q
latanoprost (PGF2a)
A
prostaglandin that increases outflow of aqueous humor
- darkens the color of the iris (browning)
7
Q
opioid analgesics (names)
A
morphine, fentanyl, codeine, loperamide, methadone, meperidine, dextromethorphan, diphenoxylate
8
Q
opioid mechanism
A
- acts as agonists at opioid receptors (mu = morphine, delta = enkephaline, kappa = dynorphin) to modulate synaptic transmission - opens K channels, closes Ca channels –> decreased transmission
- inhibit release of Ach, norepi, 5HT, glutamate, substance P
9
Q
opioid clinical use
A
- pain
- cough suppression - dextrmethorphan
- diarrhea - loperamide, diphenoxylate
- acute pulmonary edema
- methadone maintenance for heroin addicts
10
Q
opioid tox
A
- addiction, resp depression, constipation, miosis, additive CNS depression with other drugs
- tolerance does not develop to miosis and constipation
- uncommon: RUQ pain bc morphine causes smooth muscle contraction –> sphincter of oddi contraction
- tox treated with naloxone or naltrexone
11
Q
butorphanol
A
mech: mu-opioid receptor partial agonist and kappa-opioid receptor agonist, produces analgesia
- used in severe pain, causes less respiratory depression than full agonists
- can cause opioid withdrawal if the patient is also taking a full agonist
- overdose not easily reversed with naloxone
12
Q
tramadol
A
- very weak opioid agonist, also inhibits serotonin and norepi reuptake
- used in chronic pain
- tox: similar to opioids, decreases seizure threshold, serotonin syndrome
13
Q
pentazocine
A
opioid narcotic with partial agonist activity and weak antagonist activity at mu receptors
- can cause withdrawal in a dependent person
14
Q
ethosuximide
A
- used in absence seizures
- blocks thalamic T-type Ca channels
- side effects: GI, fatigue, headache, urticaria, SJS
- “sucks” to have silent seizures
15
Q
phenytoin
A
- used in all seizure types except absence, can be used in status
- increase Na channel inactivation, zero-order kinetics
- nystagmus, diplopia, ataxia, sedation, gingival hyperplasia, hirsuitism, peripheral neuropathy, megaloblastic anemia, teratogen, SLE-like syndrome, induction of cytochrome P-450, lymphadenopathy, SJS, osteopenia
16
Q
carbamezapine
A
- used in all types of seizures except absence
- increases Na channel inactivation
- SE: diplopia, ataxia, blood dyscrasias, liver tox, teratogenesis, induction of P-450, SIADH, SJS
- 1st line treatment for trigeminal neuralgia
17
Q
valproic acid
A
- used in all types of seizures, 1st line in T-C seizures
- increases Na channel inactivation, increased [GABA] by inhibiting GABA transaminase
- SE: GI distress, rare but fatal hepatotox (measure LFTs), neural tube defects, tremor, weight gain
- also used for myoclonic seizures and bipolar disorder
18
Q
gabapentin
A
- used in all types except absence seizures
- primarily inhibits high-voltage-activated Ca channels, designed as GABA analog
- SE: sedation, ataxia
- also used for peripheral neuropathy, postherpetic neuralgia, migraine prophylaxis, bipolar disorder
19
Q
phenobarbital
A
- used in all types except absence seizures
- increased GABAa action
- SE: sedation, tolerance, dependence, induction of P450, cardiorespiratory depression
- 1st line in neonates
20
Q
lamotrigine
A
- used in all types of seizures
- blocks voltage gated Na channels
- SE: SJS
21
Q
barbituates (phenobarb, pentobarb, thiopental, secobarbital) mech and use
A
- mech: facilitate GABAa action by increasing duration of Cl channel opening, thus decreasing neuron firing
- contraindicated in porphyria
- used as sedative for anxiety, seizures, insomnia, induction of anesthesia (thiopental)
22
Q
whats so special about thiopental?
A
rapidly wears off due to distribution into tissues, not because of metabolism
- barbituate used for induction of anesthesia and short surgical procedures
23
Q
barbituates toxicity
A
- resp and cardiovascular depression
- CNS depression, dependence, drug interactions (p450 inducer)
- overdose treatment is supportive
24
Q
long acting benzos
A
diazepam, flurazepam, chlordiazepoxide
25
intermediate acting benzos
LET
| lorazepam, estazolam, temazepam
26
short acting benzos
TOM
| - triazolam, oxazepam, midazolam
27
benzo mechanism
- facilitate GABAa action by increasing the frequency of Cl channel opening
- decrease REM sleep
28
benzo tox
- dependence, additive CNS depression effects with alcohol
- less risk of respiratory depression and coma than with barbituates
- treat overdoses with flumazenil (competitive GABA antagonist)
29
nonbenzo hypnotics
- zolpidem, zaleplon and eszopiclone
- act via the BZ1 subtype of the GABA receptor, effects reversed by flumazenil
- used for insomnia
- metabolized by p450
- tox: ataxia, headaches, confusion, short duration and only modest day-after psychomotor depression
- decreased risk of dependence, no muscle relaxing or anticonvulsant effects
30
MAC
minimal alveolar concentration
- lower MACs, higher potency
- drugs with increased solubility in lipids --> increased potency = 1/MAC
31
inhaled anesthetics names and effects
- halothane, enflurane, isoflurane, sevoflurane, methoxyflurane, NO
- mechanism unknown
- effects: myocardial depression, respiratory depression, nausea/emesis, increased cerebral blood flow, decreased cerebral metabolic demand, decreased GFR, decreased hepatic blood flow
32
inhaled anesthetics side effects
- hepatotox (halothane), nephrotox (methoxyflurane), proconvulsant (enflurane), expansion of trapped gas in body cavity (NO)
- can cause malignant hyperthermia, treat with dantrolene (usually due to ryanodine receptor mutation, this prevents further release of Ca)
33
midazolam
- most common drug used for endoscopy
- used adjunctively with gaseous anesthetics and narcotics
- may cause severe postop resp depression, decreased BP and anterograde amnesia
34
ketamine
- PCP analog that acts as a dissociated anesthetic
- blocks NMDA receptors
- CV stimulant
- causes disorientation, hallucination and bad dreams
- increased cerebral blood flow
35
propofol
- used for sedation in the ICU, rapid anesthesia induction, and short procedures
- less post op nausea than thiopental
- potentiates GABAa
36
local anesthetics
- block Na channels by binding to specific receptors on the inner portion of the channel
- need more in infected (acidic) tissue
- blocks small myelinated fibers > small unmyelinated fibers > large myelinated fibers > large unmyelinated fibers
- lose pain, then temp, then touch, then pressure
- tox: CNS excitation, cardiovascular tox, HTN, hypotension, arrhythmias
37
succinylcholine
- strong Ach receptor agonist
- produced sustained depolarization and prevents muscle contraction
- reversal of blockade not possible in phase I, cholinesterase inhibitors will overcome blockade in phase II (when the receptors are available but desensitized)
38
nondepolarizing neuromuscular blocking drugs
- tubocurarine, atracurium, mivacurium, pancuronium, vecuronium, rocuronium
- competitive antagonists, compete with Ach for receptors
- reversal of blockade with neostigmine, edrophonium and other cholinesterase inhibitors
39
dantrolene
- prevents release of Ca from the sarcoplasmic reticulum of skeletal muscle
- used to treat malignant hyperthermia and NMS because usually due to ryanodine receptor mutation
40
bromocriptine, pramipexole, ropinirole
dopamine agonist used in parkinsons
41
amantadine
increases dopamine release, also has antiviral activities
| - tox: ataxia
42
selegiline
- selective MAOb inhibitor that prevents dopamine breakdown
- adjunctive agent to L-dopa in treatment of parkinsons
- may enhance adverse effects of L-dopa
43
entecapone, tolcapone
- COMT inhibitors that prevent L-dopa degredation
| - entecapone inhibits peripheral destruction, and tolcapone inhibits peripheral and central destruction
44
benztropine
- antimuscarinic that improves tremor and rigidity in parkinsons but has little effect on bradykinesia
45
memantine
- NMDA receptor antagonist
- helps prevent excitotoxicity (mediated by Ca)
- tox: dizziness, confusion, hallucinations
46
donepezil, galantamine, rivastigmine
- AchE inhibitors used in alzheimers
| - tox: nausea, dizziness, insomnia
47
Huntington drugs
- NT changes: dec GABA and Ach, inc dopamine
- haloperidol - D2 receptor antagonist
- tetrabenazine and reserpine - inhibit vesicular monoamine transporter, limit dopamine vesicle packaging and release
48
sumatriptan
- serotonin agonist
- inhibits trigeminal nerve activation, prevents vasoactive peptide release, half-life < 2 hours
- used in acute migraine and cluster headaches
- tox: coronary vasospasm (contraindicated in pts with CAD and prinzmetal angina), mild tingling
