Sedatives and hypnotics Flashcards
What are the GABA-a agonists?
Benzos
Barbituates
Newer agents (zolpidem, zaleplon, eszopiclone)
Where does Buspirone act?
5-HT1a partial agonist; used for anti-anxiety
What does Ramelteon act on?
Melatonin receptor; agonist
List some of the Benzos:
- Diazepam
- Chlordiazepoxide
- Flurazepam
- Oxazepam
- Lorazepam
List some of the Barbituates:
- Phenobarbital
- Pentobarbital
- Gluthemide
- Meprobemate
What are the inhibitory NTs/receptors?
GABA, glycine, M2, M4, D2, D4
What are the excitatory NTs/receptors?
Glutamate, M1, M3, M5, D1, D5, Nicotine, NE
Where do benzodiazepines act, and do they plateau?
- The GABA-alpha and gamma subunits
2. Yes, they plateau in CNS depression
What increases the frequency of the chloride channels?
Benzos
What increases the duration of the chloride channels?
Barbituates; can activate without GABA!
Most rapid acting benzo?
Triazolam; followed by Diazepam. Benzos with long half-life also cause a more cumulative effect!
Which benzos are used in the elderly or patients with liver dysfunction?
Lorazepam, Oxazepam, Temazapam
What are the long elimination benzos, and what are they used for?
Chlorazepate, Diazepam, Flurazepam. Used for anti-anxiety; but cause more daytime drowsiness, falling, etc.
What is the shortest elimination benzo, and a side effect?
Triazolam; more withdrawal effects
Does phenobarbital cause p450 inhibition or induces it?
Induces p450! Can cause less jaundice in mothers, but don’t use in liver disease.
What are withdrawal symptoms of benzos and how do you treat it?
Anxiety, CNS depression, insomnia; treat w long acting benzos or phenobarbital
What is the antidote for benzos?
Flumazenil, has high affinity for GABA-a site, act as competitive antagonists.
What is the most toxic benzo?
Alprazolam in overdose; cause respiratory depression. Treat w/ Flumazenil, but can cause withdrawal symptoms in long time use pts.
What are the two benzos for alcohol withdrawl?
Chlordiazepoxide and Diazepam
What benzo is used for seisures?
Lorazepam due to prediction of activity
In what patients are barbituates contraindicated in?
Patients with a history of poryphria
What is used to treat an acute panic attack?
Alprazolam
What are benefits of using buspirone in anxiety?
Relieves anxiety without sedative, hypnotic, or euphoric effects, no anti-convulsant or muscle relaxant properties, and no dependence
What are the preferred agents for insomnia?
Benzos and ZZesZ’s; can also use Ramelteon
How do benzos and barbituates change sleep properties?
- Decrease latency of falling asleep
- Increase stage 2
- Decrease stage 4
- Decrease REM
What’s a side effect of benzos in insomnia?
Anterograde amnesia; and daytime sedation with long half life benzos.
How do the ZZesZ’s affect sleep?
- Zaleplon decreases sleep latency; T1/2 = short
- Eszopiclone increases total sleep time; T1/2 = 6hr
- Zolpidem most prescribed
Affect sleep architecture less; and not as strong binding to GABA thus less effect on cognitive function
What is Ramelteon used for?
MT1 & MT2 agonist used for sleep problems, decreases latency with no affect on sleep architecture; safe to use in COPD patients
What are contraindications of Ramelteon and ADRs?
- Can’t use w/ CYP1A2 (ciprofloxacin, fluvoxamine); use with caution in liver damage pts
- Decrease testosterone, increase prolactin
