Hypnotics Flashcards
Name the 3 barbituates
phenobarbital
pentobarbital
thiopental
Where do barbs bind?
in the transmembranous portion of the GABA-A receptors
What is the mechanism of barbs?
prolong duration of binding of GABA to GABA-A receptors –> promotes inhibition of neurons
Which isoforms of GABA-A do barbs bind?
all of them
What is the elimination half life of barbs from the blood?
4-5 days
How do you help barbs be excreted in the urine?
give bicarb
Why give bicarb in barb overdose?
barbs are more readily absorbed back into the blood when the blood is more acidic
Barbs cause prolonged sleep in which phase?
2
Barbs prolong/decrease REM
decrease
Barbs prolong/decrease stage 4
decrease
Fastest barb
thiopental
What is the toxic effect of barbs at high doses?
affect electrical conductivity in ALL tissues
paralysis –> arrest –> death
Benzos
diazepam
lorazepam
triazolam
alprazolam
Mechanism of benzos
bind GABA-A on extracellular surface
increase frequency of Cl- channel opening events
Barbs and liver
barbs sped up their own metabolism as well as metabolism of other drugs
Barbs: pharmacokinetic or pharmacodynamic tolerance?
both
Benzos: pharmacokinetic or pharmacodynamic tolerance?
primarily pharmacodynamic
downregulation of GABA-A receptors
Benzos cause this great effect
anterograde amnesia
Flumazenil function/mechanism
reverse benzo effect
binding site agonist
This drug is used to reverse the effects of benzos
flumazenil
Zolpidem
Zaleplon
Eszoplicone
non-benzodiazepine benzodiazepine agonists
Ezzzzz
z’s in all the names
What is so special about the zzzz drugs?
the bind a subset of GABA-A receptors
better sleep
ware off more quickly
Buspirone mechanism
partial 5-HT-1A agonst
Buspirone use
anxiety
Ramelteon mechanism
melatonin agonist
