Ch 28 Opioid Flashcards
__ are drugs that relieve pain without causing loss of consciousness.
Analgesics
__ are the most effective analgesics available.
Opioids
There are three major classes of opioid receptors, designated (3).
mu, kappa, and delta
Morphine and other pure opioid agonists relieve pain by __.
mimicking the actions of endogenous opioid peptides— primarily at mu receptors, and partly at kappa receptors.
Opioid-induced __ can complement pain relief.
sedation and euphoria
Because opioids produce __, they have a high liability for abuse.
euphoria and other desirable subjective effects
__ is the most serious adverse effect of the opioids.
Respiratory depression
Other important adverse effects of opioids are __.
constipation, urinary retention, orthostatic hypotension, emesis, miosis, birth defects, and elevation of ICP.
Because of __, oral doses of morphine must be larger than parenteral doses to produce equivalent analgesic effects.
first-pass metabolism
Because the __ is poorly developed in infants, these patients need smaller doses of opioids (adjusted for body weight) than do older children and adults.
blood-brain barrier
With prolonged opioid use, tolerance develops to __.
analgesia, euphoria, sedation, and respiratory depression, but not to constipation and miosis
Cross-tolerance exists among the various opioid agonists, but not between opioid agonists and __.
general CNS depressants
With prolonged opioid use, ___.
physical dependence develops.
An abstinence syndrome will occur if the opioid is abruptly withdrawn.
In contrast to the withdrawal syndrome associated with general CNS depressants, the withdrawal syndrome associated with __, although unpleasant, is not dangerous.
opioids
To minimize symptoms of abstinence, opioids __.
should be withdrawn gradually
Precautions to opioid use include (4).
pregnancy, labor and delivery, head injury, and decreased respiratory reserve.
Patients taking opioids should avoid alcohol and other
CNS depressants because these drugs __.
can intensify opioid induced sedation and respiratory depression.
Patients taking opioids should avoid anticholinergic drugs (e.g., antihistamines, tricyclic antidepressants, atropine-like drugs) because these drugs __.
can exacerbate opioid-induced constipation and urinary retention.
Opioid overdose produces a classic triad of signs:
coma, respiratory depression, and pinpoint pupils.
All __ are essentially equal to morphine with regard to analgesia, abuse liability, and respiratory depression.
strong opioid agonists
Use of meperidine should be avoided so as to prevent accumulation of __.
normeperidine, a toxic metabolite
Like morphine, codeine and other moderate to strong opioid agonists produce:
analgesia, sedation, euphoria, respiratory depression, constipation, urinary retention, cough suppression, and miosis.
These drugs differ from morphine in that they produce less analgesia and respiratory depression and have a lower potential for abuse.
The combination of codeine with a nonopioid analgesic (e.g., aspirin, acetaminophen) produces __.
greater pain relief than can be achieved with either agent alone
Most __ act as agonists at kappa receptors and antagonists at mu receptors.
agonist-antagonist opioids
__ produce less analgesia than morphine and have a lower potential for abuse.
Pentazocine and other agonist-antagonist opioids
With agonist-antagonist opioids, there is a ceiling to __.
respiratory depression
If given to a patient who is physically dependent on pure opioid agonists, an agonist-antagonist will __.
precipitate withdrawal.
__ act as antagonists at mu receptors and kappa receptors.
Pure opioid antagonists
___ can reverse respiratory depression, coma, analgesia, and most other effects of pure opioid agonists.
Naloxone and other pure opioid antagonists
The only exception is methylnaltrexone, which doesn’t cross the blood-brain barrier.
__ are used primarily to treat opioid overdose.
Pure opioid antagonists
Two agents—methylnaltrexone and naloxegol— are used for opioid-induced constipation, and another— alvimopan—for opioid-induced ileus.
If administered in excessive dosage to an individual who is physically dependent on opioid agonists, __ will precipitate an immediate withdrawal reaction.
naloxone
Opioid dosage must be __.
individualized.
Patients with a low tolerance to pain or with extremely painful conditions need high doses.
Patients with sharp, stabbing pain need higher doses than patients with dull pain.
Older adults generally require lower doses than younger adults.
Neonates require relatively low doses.
As a rule, opioids should be administered __ postoperatively.
on a fixed schedule for the first 24 hours postoperatively (with supplemental doses for breakthrough pain) rather than PRN.
Most PCA devices are electronically controlled pumps
that can be activated by the patient to deliver a __.
preset dose of opioid through an indwelling catheter.
Some PCA devices also deliver a basal opioid infusion.
__ provide steady plasma drug levels, thereby
maintaining continuous pain control while avoiding
unnecessary sedation and respiratory depression.
PCA devices
Use of __ can suppress uterine contractions and cause respiratory depression in
the neonate.
parenteral opioids during delivery
__ is a primary chronic disease characterized by an individual pathologically pursuing rewards and/or relief by substance use and other behaviors.
Addiction
Physical dependence and addiction are not the same.
__ is defined as drug use that is inconsistent with medical or social norms.
Abuse
Because of excessive and inappropriate fears about addiction and abuse, providers frequently prescribe __.
less pain medication than patients need, and nurses frequently administer less medication than was prescribed.
Dispel your concerns about abuse and addiction, and __.
give your patients the medication they need to relieve suffering. That’s what opioids are for, after all.
