Sedatives / Hypnotics Flashcards
1
Q
General characteristics of sedatives
A
Anxiolytics
Reduce anxiety, exert calming effect. Minimal effects on motor / cognitive functions.
Anticonvulsant effects.
2
Q
General characteristics of hypnotics
A
Produce drowsiness and promote onset / maintenance of sleep
Anticonvulsant effects
3
Q
What are the 2 main classes of sedatives / hypnotics?
A
Benzos and barbiturates
4
Q
Benzos General mechanism Effects Length of use Adverse rxns
A
- Positive modulators at GABAa receptors. Increase affinity of GABAa receptor for GABA and increase freq of GABA-induced Cl channel opening, but do NOT directly activate receptor.
- Able to produce sedating, hypnotic, anxiolytic, amnesiac, spasmolytic, and antiseizure effects, but unable to produce anesthesia / coma.
- May slightly lower BP.
- Do NOT depress respiration or induce CYP enzymes.
- Only indicated for short-term use (2-4 weeks)
- Adverse effects –
- CNS: drowsiness, ataxia, slurred speech
- Doseage should be tapered to avoid insomnia, anxiety, and seizures (withdrawal syndrome)
- May cause paradoxical excitement in kids and elderly
- Avoid during pregnancy. Category D / X.
5
Q
General mechanism of barbiturates
A
- Increase duration of GABA channel opening and directly activate receptor at high concentrations.
- Able to produce anesthesia / coma at high doses.
- Can depress respiration and induce CYP enzymes.
6
Q
Diazepam Brand name Type of drug Use 2 metabolites Why does diazepam have a longer duration of action than oxazepam? Adverse rxns Precautions
A
- Valium
- Benzo
- Use – short term management of anxiety disorders and acute alcohol withdrawal. Also acts as muscle relaxant for seizure disorders, cerebral palsy, stroke, and MS
- Mechansim – increases affinity of GABAa receptor for GABA and increases freq of GABA-induced Cl channel opening.
- 2 metabolites, desmethyldiazepam and oxazepam, are active. Diazepam has a longer duration of action than oxazepam b/c it is further upstream in terms of metabolism.
- Adverse rxns – see above
- Precautions – avoid during pregnancy and breastfeeding
7
Q
Lorazepam Brand name Type of drug Main diff from diazepam Use Mechanism Adverse rxns
A
- Ativan
- Benzo
- Main diff from diazepam – No active metabolites. Doesn’t produce a hangover / drowsiness. More potent.
- Use – anxiety disorder, preop sedation, anterograde amnesia, sedation for critical care. DOC for status epilepticus
- Mechanism – Increases affinity of GABAa receptor for GABA and increases freq of GABA-induced Cl channel opening.
- Adverse rxns – see above
8
Q
Flumazenil Type of drug Use Mechanism Pharmacokinetics Precaution
A
- Short acting benzo
- Use – treats benzo overdose or reverses benzo sedation during anesthesia. Also antagonizes zolpidem and eszopiclone. No effect on barbiturates.
- Mechanism – competes w/ benzo for binding to GABAa receptor
- Short half life. May need repeated doses.
- Precaution – may precipitate benzo withdrawal syndrome (anxiety, insomnia, seizures)
9
Q
Buspirone Type of drug Effects Good for which population? Use Mechanism Pharmacokinetics Time of onset Precautions
A
- Non-benzo anxiolytic that produces no hypnosis, anticonvulstant effects, or psychomotor impairment. Reduce anxiety w/o effecting GABA. Good in pregnant women or other people who can’t tolerate benzos.
- Use – treats GAD
- Mechanism – Partial agonist at 5HT1a receptors. Moderate affinity and partial agonist at D2 receptors.
- Low bioavailability.
- Significant latency, taking 2-6 weeks to work. Not good for acute anxiety.
- Precautions
- Taper off benzos as buspirone is initiated.
- Renal insufficiency
- Hepatic disease
10
Q
Transient insomnia
Length
Cause
Tx
A
Lasts less than 3 days.
Caused by brief environmental / situational stressor.
May respond to sleep hygiene rules
11
Q
Short-term insomnia
Length
Cause
Tx
A
3 days to 3 weeks.
Caused by stressors.
Tx w/ intermittent use of hypnotics for 7-10 days
12
Q
Long-term insomnia
Cause
A
Lasts more than 3 weeks.
Caused by major psychiatric illness (mania), sleep apnea, or chronic medical illnesses (CHF). May also be due to “learned” insomnia.
13
Q
Zolpidem Brand name Type of drug Use Mechanism Adverse rxns
A
- Ambien
- Non-benzo sedative / hypnotic
- Use – short term tx of insomnia (7-10 days)
- Mechanism – Modulates GABAa receptor complex
- Adverse rxns: overall well-tolerated (no hangover effect). Rebound insomnia. Sleep walking.
14
Q
Eszopicolone Brand name Type of drug Comparison to zolpidem Use Mechanism Adverse rxns
A
- Lunesta
- Non-benzo sedative / hypnotic.
- More potent than zolpidem.
- Use – 1st drug approved for long-term treatment of insomnia (>6 months)
- Mechanism – modulates GABAa receptor complex
- Adverse rxns – well tolerated overall (no hangover). Rebound insomnia, anxiety, unpleasant taste, xerostomia.
15
Q
Aprazolam
Brand name
Type of drug
A
Xanax
Potent benzo
