Slides 5 Flashcards
What is a common feature of sedative-hypnotic use ?
Tolerance
What occurs among the sedative-hypnotics and also with ethanol ?
Partial cross-tolerance
An increase in what may contribute to tolerance with barbiturates ?
Drug metabolism
With benzodiazepines, tolerance may be due to:
Down regulation of brain BDZ receptors
Tolerance can occur with extended use of?
Zolpidem, but much less so with zaleplon and eszopiclone.
What is the cause of the compulsive use of virtually all sedative-hypnotics?
The perceived relief of anxiety, euphoria, disinhibition, and promotion of sleep
The consequences of abuse can be both?
Psychologic and physiologic.
What happens when the pattern of sedative-hypnotic use becomes compulsive?
More serious complications develop, including tolerance and physiologic dependence.
What is Physiologic dependence?
An altered physiologic state that requires continuous drug administration to prevent an abstinence or withdrawal syndrome.
Abstinence or withdrawal syndrome consists of?
1) Increased anxiety
2) Restlessness
3) Insomnia
4) CNS excitability that may progress to:
a) Convulsions
b) Weakness
c) Orthostatic hypotension
What is the difference between drugs with long half-life and short half-life in terms of withdrawals?
Drugs with long half-life are eliminated slowly enough to accomplish gradual withdrawal with few physical symptoms.
Drugs with short half-lives may show signs of withdrawal even between doses (triazolam).
True of False:
Withdrawal symptoms of zolpidem, zaleplon, or eszopiclone are more intense than that with BDZs
False; it is less intense
True of False:
Lethal dose range is not altered significantly by long-term use
True
True of False?
The degree of tolerance achieved is identical for all pharmacologic effects
False; it is not identical
What can cross-tolerance between different sedative-hypnotics, including ethanol, lead to?
Unsatisfactory therapeutic response when standard doses of a drug are used in a patient with a recent history of excessive use of another agent.
What is Flumazenil? What type of drug is it?
A benzodiazepine derivative with high affinity for BDZ binding sites on GABAA receptor; Competitive antagonist.
Flumazenil blocks many of the actions of ?
BDZs, zolpidem, zaleplon, and eszopiclone.
True of False ?
Flumazenil does not antagonize the CNS effects of other sedative-hypnotics, ethanol, opioids or general
anesthetics.
True
Flumazenil is used for:
1) Reversing the CNS effects of BDZ overdose
2) Hastening recovery following use of BDZ in anesthesia and diagnostic procedures.
True of False:
Antagonism of BDZ-induced respiratory depression is more predictable.
False; it is less predictable
What is Flumazenil’s half-life?
It has a short half-life due to rapid hepatic clearance (0.7-1.3 hours)
What are the adverse effects of Flumazenil?
1) Agitation, confusion, dizziness, and nausea.
2) Severe abstinence syndrome in patients with physiologic dependence
3) Seizures and cardiac arrhythmias in patients who have ingested benzodiazepines with tricyclic antidepressants
What are the therapeutic effects of sedative-hypnotic drugs?
1) Relief of anxiety states (cause still needs to be treated)
2) Treatment of insomnia
3) Sedation and amnesia before and during medical and surgical procedures
4) Epilepsy and seizures (termination of an attack)
5) As a component of balanced anesthesia (IV)
6) For control of ethanol or other sedative-hypnotic withdrawal states
7) For muscle relaxation in specific neuromuscular disorders
8) Suppression of delirium tremens (alcohol withdrawal)
9. Drug-induced hyperexcitability states
Which sedative-hypnotic drug is used to relieve anxiety (panic disorders and agoraphobia)?
Alprazolam
Which drugs are preferred for insomnia?
Benzodiazepine and the newer agents over barbiturates
Which drug is used for sedation and amnesia before and during medical and surgical procedures?
Midazolam
Which drug is given for suppression of delirium tremens (alcohol withdrawal)?
Parenteral lorazepam
What are the adverse effects of sedative-hypnotic drugs?
1) Relatively low doses may lead to drowsiness,
impaired judgment, and diminished motor skills
2) BDZ may cause a significant dose-related anterograde amnesia
3) Confusional states (especially in the elderly)
4) Hangover effects
5) At higher doses, may produce lethargy or a
state of exhaustion, or symptoms equivalent to
ethanol intoxication
6) Exacerbation of breathing problems in patients
with chronic pulmonary disease and those
with symptomatic sleep apnea
7) Cardiovascular collapse
8) Extensive clinical use (triazolam) has caused
behavioral disinhibition, delirium, aggression,
and violence.
9) Hypersensitivity reactions.
10) Teratogenicity
What do many of the adverse effects of sedative-hypnotics result from?
CNS depression
What causes confusional states from sedative-hypnotic drugs?
Overuse of sedative-hypnotics