Terms in this set (58)
Alprazolam, Chlordiazepoxide, Clonazepam, Clorazepate, Diazepam, Estazolam, Flurazepam, Lorazepam, Midazolam, Oxazepam,Temazepam, Triazolam
"Facilitates inhibitory actions of GABA by binding allosteric site on GABA-A receptor-chloride ion channels between α and γ subunits ; increases FREQUENCY of chloride channel opening = influx of chloride ions = hyperpolarization of neuronal membrane = Counteracts excitatory neurotransmitters"
Benzodiazepines dose-response in terms of CNS depression
"Dose-dependent CNS effects - to a point = Ceiling effect; Only work in presence of GABA and can inhibit GABA release ; Ceiling effect negated by concomitant use of other CNS depressants (e.g., alcohol) ; Favorable safety profile vs. barbiturates"
Therapeutic effects of benzodiazepines (4)
Sedation, hynosis, anticonvulsant effects, muscle relaxation
Adverse effects of benzodiazepines
"CNS depression - drowsiness, dizziness, motor incoordination, impaired cognitive processes, impaired psychomotor skills, behavioral disinhibition ; Anterograde amnesia - cannot recall what happens when drug is taking effect ; Rare - arrhythmias, hypotension, and mild respiratory depression ; Dependence and tolerance - taper upon discontinuation to prevent withdrawal ; Abuse potential - history of drug abuse = greater risk"
Benzodiazepine receptor antagonist
Benzodiazepines that are preferred in elderly (3). Why?
"Lorazepam, Oxazepam, and Temazepam (L.O.T.) Do not undergo phase I metabolism"
Most but not all benzodiazepines undergo phase ___ metabolism via CYP450 to ___ metabolites
Phase I; active
Benzodiazepines with a short duration of action (1-6 hours) (4)
"Clorazepate, Oxazepam, Triazolam, Midazolam"
Benzodiazepines with a medium duration of action (7-12 hours) (5)
Alprazolam; Clonazepam; Lorazepam; Temazepam; Estazolam
Benzodiazepines with a long duration of action (> 12 hours) (3)
Chlordiazepoxide, diazepam, flurazepam
Benzodiazepine indications aside from acute anxiety and insomnia (5)
"Alcohol detoxification (several) ; Seizure disorders/status epilepticus (several); Muscle spasms; spasticity (diazepam); Anesthesia (midazolam)"
Benzodiazepine contraindications (2)
Benzodiazepine precautions (6)
"Pregnancy (triazolam and estazolam are contraindicated) ; Liver dysfunction; Renal dysfunction; Respiratory insufficiency; sleep apnea; History of drug abuse; Elderly (start low and titrate slow)"
Benzodiazepine major drug interactions (~3)
"Other CNS depressants - additive effects (alcohol, barbiturates, opioids, tricyclic antidepressants); Potent 3A4 inhibitors - increase levels of: alprazolam
| diazepam | midazolam | triazolam
|| *concomitant use is contraindicated ; Potent 3A4 inducers - decrease levels of: alprazolam | diazepam | midazolam | triazolam"
Non-benzodiazepine benzodiazepine receptor agonists
Zolpidem; zaleplon; eszopiclone
Indication for non-BZ BZ receptor agonists?
Which non-BZ BZ receptor agonist is indicated for mid-sleep awakenings?
When should non-BZ BZ receptor agonists be taken
Immediately prior to bed
Rank safety profile of barbiturates, benzodiazepines, and non-BZ BZ receptor agonists in terms of CNS depressant effects (safest to least safe)
Non-BZ BZ receptor agonists > benzodiazepines > barbiturates
MOA of non-BZ BZ receptor agonists
Same as benzodiazepines, except more selective for GABA-A receptors with alpha-1 subunit
Non-BZ BZ receptor agonists contraindication and precautions
Contraindication = hypersensitivity; precautions = liver dysfunction, elderly
Major drug interactions with non-BZ BZ rececptor agonists
"Other CNS depressants - additive effects (alcohol, barbiturates, opioids, tricyclic antidepressants)"
non-BZ BZ recptor agonists common adverse effects
"Dizziness, drowsiness, headache, difficulty with coordination ; Eszopiclone can cause disorder of taste (metallic taste)"
Barbiturates mentioned in class (4)
Amobarbital; pentobarbital; phenobarbital; thiopental
Which (2) barbiturates mentioned in class are indicated for insomnia
MOA of barbiturates
"Bind allosteric site on γ-aminobutyric acid-A (GABAA) receptor-chloride ion channels (not BZ receptor) ; Increases DURATION of chloride channel opening = influx of chloride ions = hyperpolarization of neuronal membrane = counteracts excitatory neurotransmitters"
Barbiturates dose-response in terms of CNS effects
Dose-dependent effects with no ceiling effect; can work in GABA's absence
Barbiturates major drug interactions (~2)
"Induce formation of liver microsomal enzymes (i.e., CYP450) that metabolize drugs = increased potential for drug interactions; other CNS depressants - additive effects"
Barbiturates contraindications (2)
Barbiturates precautions (6)
"Pregnancy ; Liver dysfunction; Renal dysfunction; Respiratory insufficiency; History of drug abuse; Elderly (start low and titrate slow)"
Barbiturates common adverse effects (~4)
"CNS depression ; Respiratory depression; Dependence and abuse potential; Withdrawal symptoms upon discontinuation - taper"
Antihistamines mentioned in class (3). Which are availble OTC?
Diphenhydramine (OTC); doxylamine (OTC); hydroxyzone (Rx only)
MOA of antihistamines (~2)
"Competitively antagonize histamine H-1 receptors ; Reduce acetylcholine release in reticular activating system = Anticholinergic effects"
Antihistamines contraindications (2)
Hypersensitivity; nurshing (diphenhydramine)
Elderly - low and slow
Antihistamines major drug interactions (~1)
Other CNS depressants
Antihistamines common adverse effects (~1)
"Anticholinergic (e.g., blurred vision, dry mouth, urinary retention, dizziness, drowsiness)"
How is melatonin sold as a commercial product?
OTC as dietary supplement, not FDA approved drug
Describe endogenous melatonin
"Neuroendocrine hormone made by pineal gland ; Interacts with melatonin (MT) receptors ; Thought to be primary mediator of circadian rhythms (sleep-wake cycle) ; Increased release before sleep onset produces drowsiness"
Sleep onset insomnia
"MT1 and MT2 receptor agonist in suprachiasmatic nuclei of CNS"
Ramelteon - withdrawal, abuse, dependence
"Minimal rebound insomnia or withdrawal symptoms upon d/c ; Minimal abuse and dependence potential"
Ramelton major drug interactions (~3)
CNS depressants - additive; metabolized by multiple CYP enzymes = potential drug interactions; contraindicated with fluvoxamine
Ramelteon contraindictions (2)
Hypersensitivity; Use with Fluvoxamine (SSRI - increases ramelteon levels)
Ramelten common adverse effects (~3)
"dizziness, fatigue, and endocrine changes leading to decreased testosterone and increased prolactin"
Chloral hydrate (~6 points)
Indicated for insomnia and sedation; Rarely used today; Prodrug activated by liver - GABA agonist; Contraindications - Hypersensitivity, liver or renal dysfunction; Major drug interactions - Other CNS depressants; Adverse effects - GI upset (nausea, vomiting, diarrhea), arrhythmias. respiratory depression
Indicated for ____, suvorexant antagonizes ____ receptors.
Insomnia; orexin (peptide involved in wakefulness)
Suvorexant drug interactions (~2)
CNS depressants - additive; potent CYP3A4 inhibitors (increases levels)
Suvorexant common adverse effects (3)
Dizziness, dry mouth, headache
Why is buspirone referred to as an atypical sedative-hypnotic?
Has anxiolytic activity but no sedation and minimal CNS depression
MOA of buspirone (~1)
"Exact mechanism unknown : partial agonist at 5-HT1A subclass of brain serotonin receptors ; moderate affinity for dopamine-2 (D2) receptors in the brain"
Onset of action of buspirone
Slow - up to 4 weeks
Tolerance, abuse and dependence with buspirone
Buspirone major drug interactions
Potent 3A4 inhibitors - increase levels
Common adverse effects of buspirone (4)
Dizziness, headache, tachycardia, GI upset
Propranolol use in terms of acute anxiety
"Often used for stage fright or acute situational/performance anxiety ; Inhibits physiologic manifestations (e.g., tachycardia)"
Beta-adrenoceptor antagonist (i.e., Beta-blocker)