Sedative Hypnotics

Question 1

why are benzodiazepines less lethal than barbituates?

Answer 1

benzos are less likely to make you stop breathing- they level off with anesthesia-like effects; barbituates and alcohols can decrease respiration, and induce coma

Question 2

describe the similarities and differences of MOA of barbituates and benzodiazepines

Answer 2

benzos- bind between a and y subunit; increase FREQUENCY of Cl- channel opening

barbituates- bind to multiple isoforms in separate site; increase DURATION of Cl- channel opening

Question 3

list the benzodiazepines that don’t require oxidative metabolism and which patients that would be important for

Answer 3

LORAZEPAM, oxazepam, remazepam

Question 4

describe what flumazenil does, which drugs it effects, and some complications from tis use

Answer 4

flumazenil is an antagonist for the BZ binding site; blocks action of Benzos and Z drugs (not barbs, EtOH, opioids); can cause precipitated withdrawal, aka seizures, in BZD dependent patients.

Question 5

describe buspirone

Answer 5

5HT partial agonist, used only for anxiety and GAD; SLOW onset of action (2-6 weeks)

Question 6

describe ramelteon

Answer 6

agonist at MT melatonin receptors; used for INSOMNIA, no abuse potential

Question 7

describe mechanism of action of GABAa receptors

Answer 7

Cl- ion channels; hyperpolarizes neurons; inhibitory NT

Question 8

why were barbituates a frequent cause of death by OD in the 1950s?

Answer 8

low therapeutic index (LD50/ED50 = 10

Question 9

what conditions are contraindications for barbituates?

Answer 9

porphyria patients; also induces CYP450 enzymes, so many drug interactions occur with barbs