Neuro drugs Flashcards
pentazocine uses
analgesia for moderate to severe pain
pentazocine AE’s
Can cause opioid withdrawal symptoms if patient is also taking full opioid antagonist (competition for opioid receptors)
butorphanol mechanism
K-agonist + mu- partial agonist
butorphanol uses and caveat
1) severe pain (eg, migraine, labor).
2) less respiratory depression than full opioid agonists.
butorphanol AE’s
1) withdrawal
2) overdose not easily reversed with naloxone
tramadol MOA
1) weak opioid agonist
2) inhibits 5-HT and NE reuptake.
tramadol use
chronic pain
tramadol AE’s
1) decreases seizure threshold
2) serotonin syndrome
ethosuximide AE’s
Fatigue Gi distress Headache Itching stevens-johnson syndrome
receptor targeted by benzos
GABA A (increase)
other use for benzos?
eclampsia seizures
phenobarbital receptor
GABA *A (increase)
1st line treatment for seizures in neonates?
phenobarbital
other drug like phenytoin?
fosphenytoin
teratogenic syndrome caused by phenytoin…
fetal hydantoin syndrome
phenytoin AE’s
1) nystagmus
2) diplopia
3) ataxia
4) sedation
5) peripheral neuropathy
6) hirsutism
7) SJS
8) gingival hyperplasia
9) DRESS syndrome
10) osteopenia
11) SLE-like syndrome
12) megaloblastic anemia
DRESS syndrome
o Code: Anna by the counter: /Drug Reaction with Eosinophilia and Systemic Symptoms. She’s sweating profusely + face is edematous + she’s topless with a morbilloform rash + has an edematous face/presentation = fever + generalized lymphadenopathy + facial edema + diffuse morbilliform skin rash. Bennett behind the counter + ryan O’connell + big aloe plant in the middle of the store + Ivan + bathtub of minos + geyser going off by entrance/associated with anticonvulsants (phenytoin + carbamazepine) + allopurinol + sulfonamides (sulfasalazine) + minocycline + vancomycin. Giant Andrew black standing in corner/MOA = thought to be drug-induced herpesvirus reactivation followed by clonal expansion of T cells that cross-react with the drug. /typically occurs 2-8 weeks after exposure to high-risk drugs.
o Location: Urban Outfitters in Portland, walls lined with dresses
osteopenia
Condition in which bone mineral density is lower than normal. Precursor to osteoporosis.
Carbamazepine AE’s
1) diplopia
2) ataxia
3) agranulocytosis + aplastic anemia
4) liver toxicity
5) teratogenic
6) SIADH
7) SJS
valproic acid mechanism
1) increased Na channel inactivation
2) *increased GABA concentration by inhibiting GABA transaminase
valproic acid AE’s
1) GI distress
2) hepatotoxicity
3) pancreatitis
4) NTDs
5) tremor
6) weight gain
vigabatrin mechanism
Increases GABA by irreversibly inhibiting GABA transaminase
Gabapentin MOA
GABA analog that primarily inhibits high-voltage-activated Ca2+ channels.
Gabapentin AE’s
sedation + ataxia
other uses for gabapentin?
peripheral neuropathy
treatment for postherpetic neuralgia?
Gabapentin
topiramate MOA
1) blocks sodium channels
2) increases GABA action
topiramate AE’s
1) sedation
2) mental dulling
3) kidney stones
4) weight loss
levetiracetam MOA
unknown; may modulate GABA and glutamate release
tiagabine MOA
Increases GABA by inhibiting reuptake.
First line for simple partial seizures?
carbamazepine
First line for simple complex seizures?
carbamazepine
First line for tonic-clonic seizures
Phenytoin
OR
Valproic acid
first line for acute status epileptics?
benzos
first line for status epilepticus prophylaxis?
phenytoin/fosphenytoin
Drugs used only for partial seizures?
vigabatrin
gabapentin
tiagabine
other barbiturate?
secobarbital
barbiturates target..
GABA*A
When are barbiturates contraindicated?
porphyria
barbiturates uses
1) sedative for anxiety
2) seizures
3) insomnia
4) thiopental used for induction of anesthesia
barbiturate overdose treatment?
supportive (assist respiration + maintain BP)
barbiturates AE’s
1) respiratory/CV/CNS depression
2) dependence
What is the GABA A receptor?
Ligand-gated Cl- channel
General pharmacokinetic rule about Benzos…
Most have long half-lives and active metabolites except (ATOM –> alprazolam, triazolam, oxazepam, midazolam, which are all short acting)
Problem with short acting benzos?
Higher addictive potential
benzos to use for status epilepticus
lorazepam
*diazepam
other use for benzos
hypnotic for insomnia
Risk of flumazenil?
Can precipitate seizures by causing acute benzo withdrawal.
nonbenzo hypnotics…
zolpidem
zaleplon
esZopiclone
nonbenzo hypnotics MOA
act via BZ1 subtype of GABA receptor
nonbenzo hypnotics antagonist
flumazenil
Nice thing about nobenzo hypnotics…
Don’t affect sleep cycle as much and unlike older sedative-hypnotics, cause only modest day-after psychomotor depression and a few amnestic effects. Also less risk of dependence.
nonbenzo hypnotics
1) ataxia
2) headaches
3) confusion
nonbenzo hypnotics pharmacologic caveat
Short duration because of rapid metabolism by liver enzymes
What determines recovery time?
Decreased solubility = more rapid recovery time
What determines potency?
solubility in lipids. INCREASED solubility = higher potency (can cross BBB better)
potency for anesthetics described by..
1/MAC
What is MAC?
minimal alveolar concentration required to prevent 50% of subjects from moving in response to noxious stimuli
Nitrous oxide pharmacokinetics
Decreased blood and lipid solubility. Thus has a fast induction and low potency.
Halothane pharmacokinetics
High lipid and blood solubility and thus high potency and slow induction.
