Module 3 - CNS Depressant Agents

Question 1

CNS depression

Answer 1

continuum ranging from relaxation, to sedation, to the induction of sleep and anesthesia

Question 2

CNS depressants uses

Answer 2

anesthesia and to treat anxiety, sleep and seizure disorders

Question 3

CNS classes

Answer 3

Barbiturates
Benzodiazepines
Miscellaneous drugs

Question 4

sedatives

Answer 4

inhibit CNS to Reduce nervousness, excitability, irritability without causing sleep

Question 5

hypnotics

Answer 5

calm and sooth CNS causing sleep

-sedatives administered in high doses become hypnotics

Question 6

sedative-hypnotic

Answer 6

• At low doses, calm or soothe the CNS without inducing sleep
• At high doses, calm or soothe the CNS to the point of causing sleep

Question 7

what does the limbic system control?

Answer 7

emotions

Question 8

reticular activation system

Answer 8

processes that trigger anxiety, restlessness, sleep

Question 9

hypothalmus regulates

Answer 9

homeostasis

Question 10

what is the job of reticular formation

Answer 10

sends info to hypothalmus

Question 11

Gamma-Aminobutyric Acid (Gaba)

Answer 11

• anti-anxiety neurotransmitter produced by glutamate
• decreased levels cause brain nerves to be overactive and transmit quickly
• sensitive fight or flight (need sm GABA to initiate normally)
• characterized by nervousness, mental strain, fear, worry and a variety of anxiety disorders

Question 12

insomnia includes

Answer 12

Difficulty falling asleep
Staying asleep
Non-restorative sleep
In combination with daytime dysfunction or distress

Question 13

insomnia associated with

Answer 13

anxiety
short term - stress
certain foods/ drinks

Question 14

consequences of insomnia

Answer 14

depression, manic disorders, chronic pain

Question 15

rebound insomnia

Answer 15

caused by discontinuation of long term use of sedatives without weening off

Question 16

Barbiturates

Answer 16

hypnotic, sedative, anticonvulsant, anesthesia for surgical procedures

• narrow therepeutic index
• not used very often

Question 17

barbiturate uses

Answer 17

Used for reoxidation and uncontrollable seizures put people into barbiturates coma until enough seizure drugs are in blood and then take out of coma

Question 18

issues with barbituates

Answer 18

Increases metabolism of other drugs, affects liver
High chance of abuse and addiction
Suppress
Affects the heart

Question 19

barbituates
category: Ultrashort
route, onset and duration

Answer 19

route - IV
onset - less than 15 mins
duration - 2 hours
example - methohexital, thiamylal, thiopental

Question 20

barbituates
category: short
route, onset and duration

Answer 20

route- PO
onset - 15-20 min
duration - 2-4 hours
examples- pentobarbital, secobarbital

Question 21

barbituates
category: Intermediate
route, onset and duration

Answer 21

route - PO
onset - 20-30 min
duration - 2-4 hours
example - butabarbital

Question 22

barbituates
category: long
route, onset and duration

Answer 22

route - PO
onset - 30-60 min
duration - 6-8 hours
example - phenobarbital, mephobarbital

Question 23

barbituates

mechanism of action

Answer 23

Site of action
-Inhibits brain impulses from passing through limbic and reticular activating systems (brain stem)

• Bind to GABA receptor-chloride channel molecule
• By inhibiting GABA, nerve impulses traveling in the cerebral cortex are also inhibited

Question 24

barbituates

effects

Answer 24

-Low doses: sedative effects
-High doses: hypnotic effects and lowers respiratory rate
-Notorious enzyme inducers
Stimulate liver enzymes that cause the metabolism or breakdown of many drugs

Overdose: respiratory depression to arrest; CNS depression (sleep to coma to death)
Can be therapeutic (e.g., anesthesia induction; uncontrollable seizures)

Question 25

barbituates | side effects on nervous system

Answer 25

nervous system: Drowsiness, lethargy, vertigo, mental depression, coma

Question 26

barbituates | side effects on cardio vascular system

Answer 26

Vasodilatation and hypotension, especially if given to fast

Question 27

barbituates | side effects on respiratory

Answer 27

Respiratory depression, apnea, bronchospasms, cough

Question 28

barbituates | side effects on GI

Answer 28

nausea/vomiting, diarrhea, constipation

Question 29

barbiturate side effects on Hematology

Answer 29

Agranulocytosis, thrombocytopenia, megaloblastic anemia

Question 30

barbiturate | general side effects

Answer 30

``` Hypersensitivity reactions (rash, fever, urticaria, etc.) **Reduced REM sleep resulting in agitation and inability to deal with normal stress ```

Question 31

barbiturate | drug interactions

Answer 31

Additive effects -ETOH, antihistamines, benzodiazepines, narcotics, tranquilizers Inhibited metabolism -MAOIs will prolong effects Increased metabolism -Reduces anticoagulant response, leading to possible clot formation

Question 32

Benzodiazepines

Answer 32

sedative-hypnotic or anxiolytic - used for short-term treatment of insomnia caused by anxiety (sedative-hypnotic) - safe but can still cause tolerance

Question 33

Benzodiazepines | Indications

Answer 33

sedation, sleep induction, skeletal muscle relaxation, anxiety relief, treatment of alcohol withdrawal, agitation, depression, epilepsy, balanced anesthesia

Question 34

what is the problem with benzodiazepines with high potency and short 1/2 life

Answer 34

moe likely to lead to problems with dependence | ex) lorazepam, oxazepam and loprazolam

Question 35

what is the problem with benzodiazepines with long 1/2 life

Answer 35

residual effects into the following day (feel hungover) | ex) withdrawal less likely

Question 36

what type of benzodiazepine has the least issues

Answer 36

intermediate

Question 37

benzodiazepine | mechanism of action

Answer 37

- Depress CNS activity - Affect hypothalamic, thalamic, and limbic systems of the brain - Benzodiazepine receptors - Do not suppress REM sleep as much as barbiturates do - Do not increase metabolism of other drugs

Question 38

benzodiazepines | drug effects

Answer 38

- Calming effect on the CNS - Useful in controlling agitation and anxiety - Reduce excessive sensory stimulation, inducing sleep - Induce skeletal muscle relaxation

Question 39

benzodiazepines | side effects

Answer 39

``` *Mild and infrequent Headache Drowsiness Dizziness Vertigo Lethargy Paradoxical excitement (nervousness) “Hangover effect” ```

Question 40

benzodiazepine antidote

Answer 40

flumazenil | *has a short half-life - must administer more than once

Question 41

when are benzodiazepines dangerous?

Answer 41

when taken with other sedatives or alcohol

Question 42

what are miscellaneous CNS depressants?

Answer 42

not benzodiazepines or barbiturates | -treat social anxiety disorder

Question 43

must use CNS depressants cautiously in....

Answer 43

the elderly Those with suicidal potential Those with impaired renal or liver function pts