CNS Pharma

Question 1

GABAa activation –> ——-

GABAb activation —> —–

Answer 1

GABAa activation leads to incr Cl- INFLUX
GABAb activation lead to incr K+ efflux
both —> more neg inside the cell meaning HYPERPOLarization meaning INHIBITORY

Question 2

Baclofen

Answer 2

GABAb agonist used in spasticity

Question 3

What is the difference btw mechanism of action of BZs and barbiturates?

Answer 3

• BZs potentiate GABA, incr FREQ of GABA opening, no GABA mimetic activity
• barbiturates prolong GABA activity, incr duration of Cl- channel opening, have GABA mimetic activity at high doses

Question 4

Benzodiazepine mechanism of action

Answer 4

• potentiates GABA
• increases FREQ of GABA opening
• NO GABA mimetic activity

Question 5

Barbiturates mechanism of action

Answer 5

• prolong GABA activity
• increase duration of Cl- channel opening
• GABA mimetic at high dose

Question 6

BZ1 mediates

Answer 6

sedation

Question 7

BZ2 mediates

Answer 7

antianxiety and impairment of cognitive fxn

Question 8

drugs that end in -azolam or azepam

Answer 8

are benzodiazepines

Question 9

drugs that end in -barbital or -pental

Answer 9

are barbiturates

Question 10

benzodiazepines end in the suffix

Answer 10

-azolam, -azepam

Question 11

barbiturates end in the suffix

Answer 11

-barbital or -pental

Question 12

long-acting BZs are good for

Answer 12

anxiety and panic disorder

Question 13

short-acting BZs are good for

Answer 13

sleep disorder

Question 14

ultra-short acting BZs are good for

Answer 14

pre-op sedation and anesthesia

Question 15

midazolam

• type of drug?
• use?
• unique features?

Answer 15

ULTRA-SHORT t1/2 BZ metabolized to active compound by liver
therefore used for pre-op sedation and anesthesia
*IV

Question 16

lorazepam

• type of drug?
• use?
• unique features?

Answer 16

BZ w/ long t1/2 and predictable kinetics therefore can use for status epilepticus
- also used for anxiety and pre-op sedation

Question 17

diazepam

• type of drug?
• use?
• unique features?

Answer 17

• BZ w/ long t1/2 and liver metabolized to active compounds which makes its kinetics less predictable
• used for anxiety, pre-op sedation, muscle relax, WITHDRAWAL states (to alcohol)
• IV

Question 18

Phenobarbital

• type of drug?
• use?

Answer 18

barbiturate used for seizures

b/c it’s long-acting

Question 19

thiopental

Answer 19

barbiturate used for induction of anesthesia

b/c ultra-short acting

Question 20

some important things about barbiturates

Answer 20

• general INDUCERS of cytochrome P450 (incr # P450 –> incr Vmax)
• contraindicated in porphyrias
• induce metabolism of most lipid-soluble drugs (OCPs, carbamazepine, phenytoin, warfarin, etc)

Question 21

GABAa drugs are additive with other CNS depressants

• example of other CNS depressant include . . .
• consequence of adding . . .

Answer 21

• CNS depressants include anesthetics, antihistamines, opiates, beta-blockers
• combo can –> life-threatening respiratory distress

Question 22

Buspirone

Answer 22

• no effect on GABA
• 5-HT1A partial agonist (meaning by self, behaves as agonist; in presence of agonist, behaves as a blocker)
• used for generalized anxiety disorder
• non-sedative
• 1-2wks to see effects

Question 23

Non-BZs used in sleep disorders

Answer 23

think ZZZ=sleep 
Zolpidem, Zaleplon, EsZopiclone
- BZ1 receptor agonist 
- less effect on cognitive fxn (b/c not BZ2)
- less tolerance & abuse liability

Question 24

BZ withdrawal signs

Answer 24

• rebound insomnia
• anxiety
• seizures when used as antieplipetic or in HIGH dose

Question 25

Barbs and EtOH

Answer 25

• anxiety
• agitation
• life-threatening seizures (delirium tremens with EtOH)

Question 26

Flumazenil

Answer 26

used to reverse BZ overdose (can’t for barbs & alcohol)