Anxiolytic and Hypnotic Drugs Flashcards
Fluoxetine (Proxac)
MOA
SSRI
Duloxetine (Cymbalta)
MOA
SERT & NET
Blocker
How long does it take to see response in SSRI/SERT&NET blockers?
2-4 week delay
Barbiturate Uses
Induction of anestesia
Epilepsy
Tension/Migraine HA
Barbiturate synergism with which Drugs?
EtOH,
BZD’s,
Z drugs
opioids
Barbiturates
MOA
APLs of all GABAa receptors
Increase DURATION of GABAa channel opening
Barbiturates and tolerance
Rapid PK tolerance due to induction of CYP
Slow PD tolerance:change in receptor number and composition
Ultrashort acting barbiturate use
Induction of anesthesia
Terminal anesthesia
Intermediate acting barbiturate use
Single drug lethal injection
Long acting barbiturate use
Anti-convulsant
Long acting barbiturate example
Phenobarbital
Phenobarbital
MOA
Barbiturate:
APL of GABAa
ADRs for Barb»BZD»Zdrug
Sedation Decreased cognition Decreased REM sleep Hangover -Anterograde Amnesia -Tolerance -Dependence -Ataxia -Withdrawal
How are BZDs similar?
Therapeutic use
pharmaco action
ADRs
How do BZDs differ?
- Onset of action
- Maximal efficacy
- Lipid solubility
- Drug interactions
- Duration of action
- Metabolic pathways
- Active Metabolites
BZD MOA
- APL of GABAa receptor
- Binding increases affinity for endogenous GABA increasing FREQUENCY of channel opening
Barbiturates vs BZDs which increases duration vs frequency of channel opening
Barbiturates: Duration
BZDs: Frequency
Do BZDs directly open the chloride channel?
What is the effect of this?
No.
Difficult to produce fatal respiratory depression in normal pt
Which GABAa subunits do BZDs interact with?
Alpha: 1,2,3, or 5
Which GABAa alpha subunit is most widely distributed, most sedating
Alpha 1
Where is alpha 2 subtype localized?
What is the effect?
Limbic system (Hippocampus and Striatum) Anxiolytic
Where are alpha 3 and 5 subtypes located?
What is the effect?
Spinal chord
Muscle relaxant
Which subtype are Z drugs more selective for?
What is the effect?
Alpha 1
Good hypnotic
Poor muscle relaxant
BZD metabolism
CYP3A4 and CYP2C19
-Do not induce CYP
Do BZDs induce PK tolerance?
No. No CYP induction
BZD Withdrawal
Anxiety Psychosis ANS (N&V, CV, Sweating) Panic, Convulsions
Diazepam (Valium)
Uses
Anxiolytic,
Anticonvulsant,
Muscle Relaxant
Preanesthetic med
What is a major source in variability for BZDs with regards to half life and potency?
Metabolites.
All have different half lives and potency