CNS Depressants

Question 1

Barbiturates: Long Acting

Answer 1

Phenobarbital

Question 2

Barbiturates: Short Acting

Answer 2

Pentobarbital

Secobarbital

Question 3

Barbiturates: Ultra Short Acting

Answer 3

Thiopentone

Methohexital

Question 4

BZDs

Answer 4

Diazepam
Clonazepam
Oxazepam
Lorazepam
Flunitrazepam
Nitrazepam
Triazolam
Alprozolam
Midazolam
Chlordiazepoxide

Question 5

Newer Hypnotics

Answer 5

Zolpidem
Eszopiclone
Zaleplon

Question 6

Barbiturates MOA

Answer 6

• Prolong opening of GABAa Cl- channels
• Membrane Hyperpolarization - Inhibition
• Inhibit Glutamate

Question 7

BZDs MOA

Answer 7

• INC frequency of GABAa Cl- Channel openings
• Membrane Hyperpolarization
• *Zolpidem and Zaleplon - Act on GABAa receptors w/ Alpha 1 subunits

Question 8

Pharmacokinetics of Barbiturates

Answer 8

• INC in hepatic Drug metabolizing enzymes

Question 9

Pharmacokinetics of BZDs

Answer 9

• Conjugation: Major route of metabolism for oxazepam and lorazepam

Question 10

Actions of Sedatives/Hypnotics

Answer 10

1) Sedation, 2) Sleep, 3) Anesthesia, 4) Coma
**Dose Dependent
Ex: Pentobarbitol
- Sedation (50-100mg)
- Hypnosis (100-200mg)
- Anesthesia (300-400mg)
- Death (More than 600mg)

Question 11

Actions of Sedatives/Hypnotics (Low Doses)

Answer 11

• Reduction of Anxiety
• Drowsiness
• Impaired motor coordination
• Impaired learning and memory
• Euphoria, impaired judgement and loss of self-control
• Anterograde amnesia

Question 12

Effects on Sleep Pattern

Answer 12

• DEC sleep onset latency
• INC stage 2 = INC sleep duration
• DEC REM
• DEC Stage 4
• Discontinuation = Rebound REM, Worsening insomnia

Question 13

Anesthesia Effects

Answer 13

• High Doses
• Depresses CNS
  Thiopental, Methohexital, Diazepam, Lorazepam, Midazolam

Question 14

Anticonvulsant Effects

Answer 14

• Inhibit Epileptic electrical activity

Clonazepam, Nitrazepam, Diazepam, Phenobarbital

Question 15

Skeletal Muscle Relaxation Effects

Answer 15

• Inhibit polysynaptic reflexes

- Depression of transmission at NMJ

Question 16

Effect on Respiratory System

Answer 16

Resp Depression

Question 17

Effect on CVS

Answer 17

Hypotension

Question 18

Tolerance

Answer 18

Repeated use = DEC in responsiveness

Question 19

Psychological dependence

Answer 19

Compulsive use to relieve anxiety

Question 20

Physiologic Dependence

Answer 20

Need drug to prevent withdrawal symptoms

Question 21

Clinical Use: Insomnia

Answer 21

Flurazepam
Triazolam
Alprazolam
Zolpidem
Zolaplon

Question 22

Clinical Use: Anxiety

Answer 22

Alprazolam
Lorazepam
Clonazepam

Question 23

Clinical Use: Epilepsy

Answer 23

Phenobarbitone - GTC

Diazepam - Status Epilepticus, Tetanus, Febrile convulsions

Question 24

General Anesthesia

Answer 24

Thiopentone

Midazolam

Question 25

Other Therapeutic Uses

Answer 25

• Endoscopy, Bronchoscopy: Diazepam, Midazolam
• Premedication prior to anesthesia
• During Withdrawal from Ethanol: Diazepam, Chlordiazepoxide
• Delerium: Lorazepam
• Central Muscle Relaxants: Diazepam (spastic conditions)

Question 26

Side Effects

Answer 26

• Psychomotor Dysfunction
• Barb and BZD Hangover (long acting)
• Dementia
• Dependence
• OD
• Porphyria (Barbs)
• Worsening breathing problems (COPD, OSA)
• Drug Interactions

Question 27

Barbiturate Poisoning Tx

Answer 27

• Gastric Lavage
• O2
• IV Bicarb
• Hemodialysis
• *NARCAN WON’T WORK!**

Question 28

BZDs OD

Answer 28

• Not as fatal as Barbs

- Flumazenil: BZD Antidote