benzo Flashcards
what are the five principle effects of benzos
sedation anxiolysis anticonvulsant skeletal muscle relaxation anterograde amnesia
benzos work on __ receptor
GABA A , chloride , hyperpolarization , inhibitory
__ reverses benzos
flumazenil
do benzos induce microsomal enzymes?
no
benzos vs. barbs
less tolerance less abuse potential greater margin of safety fewer drug reactions less addiction potential
benzos give you retrograde or anterograde amnesia?
anterograde (new information)
NOT retrograde (stored information)
should you change your NMB dose due to benzos?
no, muscle relaxation due to central origin, NOT at neuromuscular junction
benzos are drugs with a __ ring fused to a __ ring
benzene ring
diazepine ring
5-aryl substituent and 1,4 diazepine ring
what is the principle INHIBITORY neurotransmitter in the CNS?
GABA
benzos enhance opening of __ gated channels resulting in __polarization and rendering them resistant to excitation
chloride gated
hyperpolarization
do benzos, barbs, and alcohol work on the same physical receptor site?
no, different sites and mechanisms, but cross tolerance possible
most common side effects of benzos?
fatigue and drowsiness
sedation usually disappears in 2 weeks
benzos have no significant BP or HR effects, but __ ventilation effects
minimal
do benzos suppress adrenal cortisol levels?
yes
two pathways for metabolism of benzos
- glucuronidation
- hepatic microsomal enzyme metabolism
glucuronidation is the exclusive pathway for 3 benzos, results in __ active metabolites, __ effect by aging
lorazepam, oxazepam, temazepam
no metabolites
little effect by aging
metabolism via hepatic microsomal enzymes produces __ metabolites and __ to aging and liver disease
active metabolites
sensitive to aging and liver disease
what is pregancy category for benzos
D or X
midazolam is __ soluble and has a __ ring where it gets its name, __ x more potent than diazepam
water soluble
imidazole ring
2-3x more potent
at pH less than 4, the imidazole ring is __ and is __ soluble
open ring
water soluble
midazolam pKa
parenteral preps of versed buffered to pH __
- 1
3. 5
when midazolam hits physio pH, the imidazole ring __ and becomes __ soluble
ring closes
lipid soluble
midazolam is prepped in water soluble preparation unlike diazepam which comes in __
propylene glycol
