Benzodiazepines Flashcards
Benzos act on which GABA subunits?
between alpha and gamma
GABA alpha 1 causes
sedation, amnesia, anticonvulsant
GABA alpha 1 found in
cerebral cortex, cerebellar cortex, thalamus
GABA alpha 2 causes
anxiolytic, skeletal muscle relaxation
GABA alpha 2 found in
hippocampus, amygdala
Besides benzos what else binds on GABA?
barbituates, etomidate, propofol, alcohol
causes risk of OD d/t synergistic effects
Midazolam IV onset
1-2 minutes
Midazolam IV peak effect
5 minutes
Midazolam IV E 1/2 time
2 hours
doubled in elderly patients…hepatic flow/enzyme activity
Midazolam IV Volume of distribution
1-1.5 L/kg (large)
increased in elderly and obese
Midazolam metabolized by
CYP3A4
active metabolite of midazolam
1-hydroxymidazolam
1/2 activity of parent
Drugs that cause inhibition of P-450 enzymes
-Cimetidine
-Erythromycin
-CCB
-Antifungal
-FENTANYL
Midazolam CNS effects
-decreases CMRO2
-Decreases CBF
-does not produce isoelectric EEG
-anticonvulsant
-Preserves vasomotor response to CO2
-No change in ICP
Midazolam pulmonary effects
-decreases ventilation (dose dependent)
-depresses swallowing reflex
-decreases upper airway activity