Anxiolytics, Sedatives, and Hypnotics Flashcards
Dose Dependent GABA receptor agonist
Barbituates (phenobarbitol)
Benzodiazepines drug list
Diazapam Triazapam Alprazolam Clonazapam Midazolam
Benzodiazepines Receptor Agonists
“Z drugs”
Zolpidem (Ambien)
Eszopiclone
Benzodiazapene Receptor Antagonists
Flumazenil
Melatonin Congener
Ramelteon
5-HT receptor agonist (non-sedative anxiolytic)
Buspirone
Sedative vs Hypnotic
Sedative - calming
Hypnotic - Sleep inducing.
Graded Dose-Response - Pentobarbitol vs Benzodiazepines
Pentobarbitol has a linear relationship - keeps on going from sedation to hypnosis to anesthesia to coma. Benzos have a proportionately higher dose required to cause coma, making them safer.
Non-antidepressant medication for Panic disorders, Agoraphobia
Alprazolam - can cause dependence and rebound anxiety when discontinued.
Non-antidepressant treatment for Social Phobia
Clonazapam
Medications for Generalized Anxiety Disorder
Benzodiazepines , Buspirone
Phenobarbitol mechanism
Direct, dose-dependent inhibition of neurons via binding to GABA receptors. Neurons become hyperpolarized due to chlorine influx and stop firing.
CYP Enzyme inducer - significant DDI’s.
Benzodiazapenes mechanism
GABA-dependent GABA receptor binding (no direct effect without GABA), increases chloride influx and membrane polarization.
Benzodiazepine receptor sensitivity
BZ binding sites are found on different subunits of GABA receptors.
alpha1 - sedation, amnesia, ataxia
alpha2,3 anxiolysis, muscle relaxation
alpha5 - cognitive impairment
Full agonist Benzodiazepines
Diazapam
Alprazolam
Zolpidem (hypnotic)
What is flumezenil used for? Why?
Benzodiazapene overdose - it binds competitively to the GABA receptor without altering its function.
Adverse effects of Benzodiazepines
Dependence, tolerance.
Respiratory depression (usually in children, pulmonary disease, or with other CNS depressants -Etoh)
CI in sleep apnea
Decreases BP, increases HR
Benzodiazepines for generalized anxiety disorder
alprazolam, diazapam
Benzodiazepines for epilepsy and muscle relaxation
clonazapam, diazapam.
Benzodiazepine that is best for anethesia - and why
midazolam - lipophilic, crosses BBB easily.
Also alprazolam, diazapam
Benzodiazepines ADME
PO (Diazapam - also IV, IM, rectal), variable duration - active metabolites produced by CYP3A4. Must be converted to glucoronides for excretion.
Does flumazenil help with etoh or barbituate overdose?
No - only Benzodiazepines
Buspirone - what makes it different from other anxiolytics?
No sedative, hypnotic, euphoric, or muscle relaxant effects. No issues with tolerance, dependence, or abuse.
Disadvantages of buspirone
Slow-acting, unpredictable response. CI with MAOI’s. Also causes chest pain, tachycardia, palpitations, dizziness, nervousness, tinnitus, GI upset.
Melatonin receptor agent - name and use.
Ramelteon - long term insomnia only.
Benzodiazapine Receptor Agonists - usefulness
“Z drugs” - sedation only - no anxiolytic, anticonvulsant, or muscle relaxation.
Benzodiazapine Receptor Agonists - advantages over Benzos for treating insomnia
Rapid acting, short duration, Less REM suppression, less tolerance,
Benzodiazapine Receptor Agonists - disadvantages
Reduced clearance in the elderly. Respiratory depression at high dose, or w/other depression. Hepatic dysfunction with cimetidine.
