Sedative and Hypnotic Drugs Flashcards
What is anxiolysis?
- Relief of anxiety
What is sedation?
- Producing relaxation, calmness, and decreased motor activity without loss of consciousness
- A side effect of many drugs that are not general CNS depressants (antidepressants, antihistamines, antipsychotics, transient with opioids)
What is hypnosis?
- Inducing drowsiness and a depressed state of consciousness resembling natural sleep, with decreased motor activity and impaired sensory responsiveness from which person is easily aroused
What is anesthesia?
- Cause a state of unconsciousness from which patient cannot be aroused
What are some clinical uses for sedative-hypnotics?
- Relief of anxiety
- Insomnia
- Sedation and amnesia before and during medical surgical procedures
- Treatment of epilepsy and seizure states
- Component of balanced anesthesia
- Control of ethanol or other sedative-hypnotic withdrawal states
- Muscle relaxation in specific neuromuscular disorders
- Diagnostic aids or for treatment in psychiatry
What is insomnia?
- Inability to fall asleep, stay asleep, get refreshed by sleeping, etc
- Widespread, affecting ~1/3 of population
- More common in women
- More common in elderly, affecting ~1/2
What is the MOA of benzodiazepines?
- Work to facilitate GABA interaction with its GABAa receptor, exact mechanism uncertain, but increases frequency of Cl- channel opening in response to GABA and gives a greater postsynaptic response to released GABA causing local hyperpolarization, meaning cell is less likely to fire
What are some clinically useful effects of benzodiazepines?
- Anti Anxiety
- Sedative-hypnotic
- Anticonvulsant
- Used to assist with alcohol withdrawal
- Amnestic
- Skeletal muscle relaxant properties
How do benzodiazepines affect the CNS?
- Produce dose dependent suppression of CNS –> drowsiness/sedation can be side effect or the desired effect
- Differences in kinetics make some agents a better hypnotic agent than anti-anxiety agent
- Anxiety relief in humans/taming in experimental animals correlates with effects in the limbic system
- Some benzodiazepines produce anterograde amnesia, the failure to retain memory for some time after drug administration
How do benzodiazepines affect the cardiovascular system?
- In healthy adults, little effect on either cardiac output or blood pressure with therapeutic doses
- Large doses cause clinically insignificant decreases in blood pressure and cardiac output
How do benzodiazepines affect the respiratory system?
- Normal doses have little effect
- Midazolam (versed), used for intravenous sedation, can cause respiratory depression and apnea
- Respiratory depressant effects are additive with other CNS depressant drugs such as opioids
What are the elimination ranges of benzodiazepines?
- 1.5-2 hours to >100 hours
What is the metabolism of benzodiazepines?
- Most undergo phase I reactions (CYP3A4) and then glucuronidation (phase II)
What are some common side effects of benzodiazepines?
- Lack of coordination
- Confusion
- Muscle weakness
- Slurred speech
- Apathy
- Dizziness
Who is most likely to suffer from side effects of benzodiazepines?
- Elderly
Who is most likely to be resistant to side effects of benzodiazepines?
- Alcoholics
- Barbiturate drug abusers
What are some paradoxic reactions in benzodiazepines?
- Excitement leading to nightmares
- Hyperactivity
- Insomnia
- Irritability
- Agitation
- Hostility/rage
Which benzodiazepines are most likely to cause amnesia?
- Short acting
What birth defects can benzodiazepines cause?
- Cleft lip
- Use during labor and delivery can cause respiratory depression
- Hypotonia
- Hypothermia in the infant
What mental and emotional changes do benzodiazepines cause?
- Confusion
- Disorientation
- Fuzzy thoughts
- Impaired memory
- Depression
- Emotional numbness
- Impaired judgement
- Losing one’s inhibitions
What physical changes do benzodiazepines cause?
- Altered vision
- Dry mouth
- Impaired motor coordination
- Poor reflexes
- Sedation
- Vertigo
- Withdrawal
- Changes in breathing
- Fatigue
- Low BP
- Nausea and/or vomiting
- Speech troubles
- Unexplainable drowsiness
What is the MOA of diazepam?
- Binds to specific GABA-A receptor subunits at CNS neuronal synapses facilitating GABA-mediated chloride ion channel opening frequency
- Enhances membrane hyperpolarization
What are the effects of diazepam?
- Dose-dependent depressant effects on the CNS including:
1. Sedation
2. Relief of anxiety
3. Amnesia
4. Hypnosis
5. Anesthesia
6. Coma
What are the toxicities of diazepam?
- Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death
- Reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate, and limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation
- Extensions of CNS depressant effects… drowsiness is common –> dangerous to operate machinery
- Dependence liability
- Interactions: additive CNS depression with ethanol and many other drugs –> death
What are some labeled clinical indications of benzodiazepine?
- Alcohol withdrawal syndrome
- Anxiety, acute/severe
- Management of anxiety disorders
- Muscle spasm, spasticity and/or rigidity
- Procedural anxiety, premedication in patients undergoing surgical/endoscopic procedures
- Seizures, acute/active
- Status epilepticus
What are some off-label clinical indications of benzodiazepine?
- Hydroxychloroquine/chloroquine toxicity
- Sympathomimetic intoxication
- Neuroleptic malignant syndrome
- Opioid withdrawal
- Serotonin syndrome
- Treatment of acute vertigo
What is the MOA of alprazolam?
- Bind to specific GABA-A receptor subunits at CNS neuronal synapses facilitating GABA-mediated chloride ion channel opening frequency
What are some effects of alprazolam?
- Dose-dependent depressant effects on the CNS including:
1. Sedation
2. Relief of anxiety
3. Amnesia
4. Hypnosis
5. Anesthesia
6. Coma
What are some toxicities of alprazolam?
- Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death
- Reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate, and limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation
- Extensions of CNS depressant effects… drowsiness is common –> dangerous to operate machinery
- Dependence liability
- Interactions: additive CNS depression with ethanol and many other drugs –> death
What are some clinical applications of alprazolam?
- Generalized anxiety disorder
- Short term anxiety
- Anxiety associated depression
- Panic disorder +/- agoraphobia
- Vertigo