sedative hypnotics

Question 1

increase the duration of the opening of the GABA-gated Cl- channel

Answer 1

thiopental
secobarbital
phenobarbital

Question 2

tolerance in barbiturates and benzodiazepines

Answer 2

Barbs rate of metabolism increases
Benzos downregulation of the binding site
Withdrawal: anxiety, insomnia, CNS excitability that can lead to convulsions

Question 3

Concerns with benzodiazepines & barbiturates

Answer 3

• CNS effects are additive with alcohol, opioids, anticonvulsants and phenothiazines (ex; chlorpromazine)
• may also have CNS depression with antihypertensives, antihistamines, tricyclics
• these can be used as hypnotics but they decrease slow wave sleep in favor of stage 2 light sleep

Question 4

MOA: hypnotic that binds to the BZ site of GABAa receptor but is not a benzodiazepine
-increases slow wave sleep
-decreases REM sleep
-shortens sleep latency while increasing total sleep time
-may experience amnesia
Adverse: get rebound insomnia if abruptly discontinue

Answer 4

Zolpidem (Ambien)

*reverse with flumazenil

Question 5

sleep medications (hypnotics)

Answer 5

Zaleplon (Sonata)
Zolpidem (Ambien)
Eszopiclone (Lunesta)
Ramelteon (Rozerem)
Buspirone (BuSpar)

*note Buspirone takes 1 week to take effect; not for acute anxiety

Question 6

Moa: melatonin receptor agonist
-reduces sleep latency without rebound insomnia or withdrawal symptoms
Adverse: somnolence (you think?), endocrine changes, decreases prolactin & testosterone
Interaction: fluvoxamine

Answer 6

Ramelteon

Question 7

MOA: hypnotics that bind to the GABAa receptor but is not a benzodiazepine
-less amnesia & day-after somnolence

Answer 7

Zaleplon

Eszopiclone

Question 8

notes on sedative-hypnotics

Answer 8

• all cross the placenta & are in breast milk
• all benzo metabolites have long half-life and can have cumulative & residual effects
• at high doses, these may depress the resp & vasomotor centers in the medulla causing coma & death
• oxazepam & lorazepam have shorter half-lives so drowsiness less pronounced

Question 9

action of benzodiazepines

Answer 9

GABA inhibition enhanced at all levels of neuro axis, including spinal cord, hypothalamus, hippocampus, SN, cerebellar cortex, cerebral cortex
-can also cause anterograde amnesia (dose dependent)

Question 10

action of barbiturates

Answer 10

less selective than benzodiazepines
bind to AMPA receptor and depress glutamate excitement
GABA enhancement & glutamate depression are why these can be used for surgical anesthesia

Question 11

Valerian root

Answer 11

can be used as anxiolytic or hypnotic

-used by some people trying to get off of sleeping pills (according to WebMD)