Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology > OPIOID ANALGESIC > Flashcards

OPIOID ANALGESIC Flashcards

1
Q

MOA of Opioid analgesics?

A

• Opioid agonists produce analgesia by activating
receptors located primarily in brain and spinal
cord involved in transmission and modulation of pain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Opioid Receptor Types?

A

• Three major classes of opioid receptors: mu, delta and kappa.
• The three are G protein linked receptors.
• The three couple to Gi.
• The majority of opioid analgesics act primarily
at the µ receptor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Relation of physiological effects to receptor type?

Supraspinal analgesia

Spinal analgesia

Respiratory depression

Reduced GI motility

Psychotomimesis

Sedation

A

Supraspinal analgesia µ,mu,delta

Spinal analgesia µ,kappa,delta

Respiratory depression µ

Reduced GI motility µ

Psychotomimesis kappa

Sedation µ,kappa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

CELLULAR ACTIONS OF OPIOIDS?

A

• The opioids have two actions on neurons:
• They close voltage-gated Ca2+ channels on
presynaptic nerve terminals.
• They open K+ channels on postsynaptic
neurons.
• Both actions reduce neurotransmitter release.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Analgesia effects due to

A
  • Inhibit ascending pain transmission.

* Activate descending pain-inhibitory circuits.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Spinal analgesia is due to opioids inhibiting?

A

Opioids inhibit ascending pain transmission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe supraspinal analgesia?

A

• The descending pain-inhibitory neurons are
inhibited by GABA.
• Opioids inhibit GABAergic neurons.
• In this way opioids activate the pain-inhibitory
descending neurons.
• This results in enhanced inhibition of pain
transmission.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pure agonists, mixed agonist-antagonist, and antagonist?

A

Pure agonists
• High affinity for mu receptors.
• Lower affinity for gamma and kappa receptors.
Mixed agonist-antagonists
• Agonist and antagonist activity on different receptors.
Antagonists
• Antagonists at all receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

CNS Effects of opioids?

A
  • Analgesia
  • Euphoria
  • Sedation and drowsiness
  • Respiratory depression
  • Cough suppression
  • Miosis
  • Truncal rigidity
  • Nausea and vomiting
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Peripheral effects of opioids?

A 
• Hypotension
• Constipation
• Contraction of biliary smooth muscle. May
result in biliary colic.
• Pruritus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Metabolism of opioids?

A

• Opioids are converted mainly to glucuronides,

which are then excreted by the kidneys.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Metabolism of morphine and Heroine?

A

Morphine is conjugated to:
• Morphine-3-glucuronide (M3G)
• Morphine-6-glucuronide (M6G)

• Heroin (diacetylmorphine) is hydrolyzed to monoacetylmorphine and to morphine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What metabolizes Codeine, oxycodone, and hydrocodone

A

• Codeine, oxycodone, and hydrocodone are
metabolized by CYP2D6.
• Codeine is converted to morphine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Metabolism of Meperidine?

A

• Meperidine is converted to normeperidine.
• Accumulation of normeperidine, may occur in
patients with decreased renal function.
• In high concentrations, normeperidine may
cause seizures.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Metabolism of Fentanyl and Methadone?

A

• Fentanyl is metabolized by CYP3A4 to inactive
metabolites.
• Methadone is metabolized by multiple P450 enzymes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Use for opioid analgesics?

A 
• Analgesia: Treatment of moderate to severe
pain.
• Acute Pulmonary Edema
• Cough
• Diarrhea
• Applications in Anesthesia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

AE of opioid analgesics?

A
  • Adverse effects of the opioid analgesics include
  • Nausea
  • Vomiting
  • Sedation
  • Itching
  • Constipation
  • Urinary retention
  • Hypotension
  • Respiratory depression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

• The most common adverse effects reported with

the use of opioid analgesics are

A
  • Nausea
  • Vomiting
  • Sedation
  • Itching
  • Constipation
19
Q

Define dependence and addiction?

A

• With frequent administration there is tolerance.
• Physiological dependence develops too.
• Dependence is defined as the occurrence of a
withdrawal syndrome.
• Physical dependence is common when opioids
are used for therapeutic purposes.
• However, addiction is not.

20
Q

Contraindications and cautions of opiods?

A

USE OF PURE AGONISTS WITH WEAK PARTIAL
AGONISTS
• When a weak agonist is given to a patient
receiving a strong agonist, there is a risk of
diminishing analgesia or even inducing a state of
withdrawal.

PATIENTS WITH HEAD INJURIES
• CO2 retention caused by respiratory depression
results in cerebral vasodilation.
• In patients with elevated intracranial pressure, this
may lead to lethal alterations in brain function.

21
Q

Contraindications and cautions of opioids continued?

A

PREGNANCY
• The fetus may become dependent.
PATIENTS WITH IMPAIRED PULMONARY
FUNCTION
• The depressant properties of the opioid
analgesics may lead to acute respiratory failure.
PATIENTS WITH IMPAIRED HEPATIC FUNCTION
• Morphine and its congeners are metabolized
primarily in the liver.
PATIENTS WITH IMPAIRED RENAL FUNCTION
• Half-life of opioids is prolonged

22
Q

Drug interactions of sedative hypnotics and MAO inhibitors?

A

Sedative-hypnotics
• Increase CNS depression, particularly respiratory depression.

MAO Inhibitors
• Some opioids inhibit serotonin reuptake: e.g.,
methadone, meperidine, tramadol, fentanyl.
• The concurrent use of these opioids and an
MAOI may trigger a “serotonin syndrome.”
• Features: Delirium, hyperthermia, headache,
hyper- or hypotension, rigidity, convulsions,
coma, and death.
• Manufacturers of opioids contraindicate the
concurrent use of MAOIs.////

23
Q

List opioid agonists?

A 
MORPHINE, HYDROMORPHONE, OXYMORPHONE
HEROIN
MEPERIDINE
FENTANYL
METHADONE
LEVORPHANOL
CODEINE, OXYCODONE, HYDROCODONE
24
Q

Describe MORPHINE, HYDROMORPHONE &

OXYMORPHONE affinities?

A
  • Useful in treating severe pain.
  • High affinity for mu receptors.
  • Lower affinity for delta and kappa receptors.
  • Morphine is the DOC for severe pain.
25
Q

Describe heroin metabolism to morphine and consequences of its metabolism?

A

• Rapidly hydrolyzed to 6-MAM, which is
hydrolyzed to morphine.
• Both heroin and 6-MAM are more liposoluble
than morphine and enter the brain more readily.
• Morphine and 6-MAM are responsible for the
pharmacological actions of heroin.

26
Q

Meperidine receptor affinity, recommendation, pk, and ae?

A

• µ receptor agonist.
• Not recommended for chronic pain due to
metabolite toxicity. Only used for short-term
treatment of acute pain.
• Meperidine has a half-life of 3 hours.
• The metabolite normeperidine has a half-life of 20 hours.
• When doses of meperidine are repeated at short intervals normeperidine accumulates.
• This leads to tremors, muscle twitches, and
seizures.

27
Q

Fentanyl affinity, pk, and use?

A
  • mu agonist.
  • Rapid onset.
  • Short duration of action (15-30 minutes).
  • 100 times more potent than morphine.
  • Used for severe pain.
28
Q

Methadone spectrum, pk, and moa?

A
  • Less euphoria than morphine.
  • Longer duration of action than morphine.
  • Effective in severe pain.
  • MOA:
  • μ receptor agonist
  • NMDA receptor antagonist
  • 5-HT and NE reuptake inhibitor
29
Q

Methadone uses?

A

• Methadone substitution is the preferred method of managing opioid withdrawal for addicted patients.
• This is because methadone has a long half-life and less profound sedation and euphoria
• Due to the long half-life of methadone, the
abstinence syndrome is prolonged but less
severe.
• Methadone is a useful drug for detoxification and
maintenance of the chronic relapsing heroin addict.

30
Q

Methadone AE?

A

• QT prolongation, torsades de pointes and death

have been reported.

31
Q

Action of Levorphanol?

A
  • μ, δ, and κ agonist.
  • Serotonin and norepinephrine reuptake inhibitor
  • NMDA receptor antagonist
  • Used in severe pain.
32
Q

Difference between oxycodone and hydrocodone?

A

• Oxycodone is used for moderate to severe pain.
Formulated alone or in combination with a
nonopioid.
• Hydrocodone is used for moderate to severe
pain. Only available in combination with
acetaminophen or a NSAID.

33
Q

Codeine use, affinity, and conversion metabolism?

A

• Codeine is used for mild to moderate pain.
• Codeine has low affinity for opioid receptors.
• The analgesic effect of codeine is due to its
conversion to morphine by CYP2D6.

34
Q

list the mixed agonist-antagonists?

A

PENTAZOCINE
BUTORPHANOL
NALBUPHINE
BUPRENORPHINE

• The mixed opioid agonist–antagonists are potent
analgesics in opioid-naive patients.
• They precipitate withdrawal in patients who are physically dependent on opioids.

35
Q

kappa agonist and a µ antagonists.

A
  • Pentazocine
  • Butorphanol
  • Nalbuphine
36
Q

Buprenorphine affinities?

A

• Buprenorphine: weak µ agonist and kappa antagonist

37
Q

PENTAZOCINE, BUTORPHANOL, NALBUPHINE &

BUPRENORPHINE recommendations and ae?

A

• Not recommended as routine analgesics,
because they have ceiling effect.
• Pentazocine, butorphanol and nalbuphine
may cause psychotomimetic effects.
• Buprenorphine is approved for management of opioid addiction.

38
Q

Tramadol actions, uses, and ae?

A 
• Weak mu agonist and norepinephrine and
serotonin reuptake inhibitor.
• Used to treat moderate pain.
• Useful in neuropathic pain.
• Increased risk of seizures in patients with a
seizure disorder.
39
Q

Naloxone and Naltrexone actions and uses?

A

• Antagonists at mu, delta, and kappa receptors.
• Naloxone is used in the treatment of acute
opioid overdose.
• Naltrexone is used for opioid and alcohol
addiction.

40
Q

High efficacy Opioids?

A 
Morphine
Hydromorphone
Oxymorphone
Methadone
Meperidine
Fentanyl
Levorphanol
Nalbuphine
Buprenorphine
Butorphanol
41
Q

Moderate-high efficacy, moderate, and low efficacy opioids?

A

Oxycodone: Moderate-High

Hydrocodone
Pentazocine:
Moderate

Codeine: Low

42
Q

ANTITUSSIVES: DEXTROMETORPHAN & CODEINE cough suppressant mechanism?

A

• Opioid analgesics are very effective for the
suppression of cough.
• This effect is often achieved at doses below
those necessary to produce analgesia.
• The receptors involved in the antitussive
effect appear to differ from those associated
with other actions of opioids.

43
Q

ANTIMOTILITY AGENTS:

DIPHENOXYLATE AND LOPERAMIDE uses, actions?

A

• Widely used in the treatment of diarrhea.
• Their actions are mediated by µ receptors on
enteric nerves, epithelial cells, and muscle.
• At usual doses, diphenoxylate and
loperamide lack analgesic effects.
• They decrease motility of smooth muscle of the
intestinal wall.

44
Q

• Pentazocine
• Butorphanol
• Nalbuphine
action?

A

Kappa agonist and a µ antagonists.

Pharmacology (49 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions