Opioids

Question 1

Differentiate between opiates and opioids

Answer 1

Opiates: derived from natural products (ex opium poppies); includes morphine, codeine

Opioids: includes opiates but also synthetic drugs and endogenous compounds with opium-like effects

Question 2

Describe the roles of the three opioid recepotors

Answer 2

delta: produces analgesia
kappa: produce analgesia through spinal sites; also produce miosis, constipation, respiratory depression, dysphoria
mu: clinically useful opioids, produce analgesia, euphoria, respiratory depression, miosis, constipation

Question 3

Describe how opioids cause analgesia

Answer 3

Opioids do not alter the pain threshold of afferent nerve endings nor the conductance of impulses; analgesia is mediated through changes in the perception of pain at the spinal cord and higher levels in the CNS and the emotional response to pain

Question 4

Opioids have no _______, meaning increasing doses have increasing incremental effects

Answer 4

ceiling effect

Question 5

Opioids are _____ by suppressing a specific center in the medulla

Answer 5

antitussive

Question 6

The most significant adverse effect of opioids is ________

Answer 6

respiratory depression

Question 7

List smooth muscle effects of opioids

Answer 7

Contraction of biliary tract smooth muscle, increased ureteral and bladder sphincter tone, decreased uterine tone, miosis

Question 8

Opioids stimulate ______ release, leading to pruritis and orthostatic hypotension

Answer 8

histamine

Question 9

List endocrine effects of opioids

Answer 9

Decreased libido, decreased production of LH–> amenorrhea, infertility, erectile dysfunction

Question 10

Differentiate between tolerance, dependence, and addction

Answer 10

Tolerance: acquired drug insensitivity, increasing doses needed to achieve the same effect

Dependence: physical and physiological requirement for continued use, withdrawal symptoms

Addiction: continued use despite harm

Question 11

Describe the syndrome of opioid withdrawal

Answer 11

Nausea, diarrhea, coughing, rhinorrhea, diaphoresis, muscle pain and cramps (5-15 days)

Neonates: hypertonicity, tremor, restlessness, vomiting, fever (1-4 days)

Question 12

______ is given to treat the autonomic hyperactivity syndromes in opioid withdrawal

Answer 12

clonidine

Question 13

____ is a strong analgesic, is a strong agonist at mu receptors, and is the DOC for MI and cancer pain

Answer 13

Morphine

Question 14

T/F: plasma concentration of morphine reliably predicts analgesic response

Answer 14

F: no predictable relationship between serum concentrations and analgesic response

Question 15

Codeine has less _____ effect and more _____ effect compared to morphine

Answer 15

less analgesic, more antitussive

Question 16

O-demethylation of codeine by ______ is essential for analgesic activity

Answer 16

CYP 2D6

Question 17

Describe the mechanism of action of buprenorphine

Answer 17

partial agonist at mu receptors, antagonist at kappa receptors

exhibits ceiling effect in pharmacological effects

Question 18

List uses for buprenorphine

Answer 18

Analgesia in opioid-naive people

Tx for opioid dependence (replacing methadone, can be prescribed in clinical office)

Question 19

______ is a competitive antagonist with little or no agonistic activity at all opioid receptors

Answer 19

Naloxone

Question 20

What is the objective of combining oxycodone with naloxone for PO delivery?

Answer 20

Discourages IV use- when used IV the naloxone will counteract the effects of oxycodone

Question 21

Meperidine

Answer 21

mu and kappa agonist, 2nd line agent for acute pain but not for chronic use

Question 22

tramadol

Answer 22

Synthetic analog of codeine; weak mu receptor agonist, also binds to NET and SERT

Question 23

hydrocodone

Answer 23

antitussive and analgesic

Question 24

methadone

Answer 24

full mu agonist with very long half life used for tx of outpatient dependence

Question 25

oxycodone

Answer 25

strong agonist, can be combined with naloxone to discourage IV use

Question 26

dextromethorphan

Answer 26

robitussin
antitussive, not analgesic. also a potent SERT inhibitor, could cause serotonin syndrome if used in combination with serotonergic drug

Question 27

loperamide

Answer 27

used as antidiarrheal because does not cross BBB

Question 28

fentanyl

Answer 28

Induction, maintenance of general anesthesia, transdermal patch or lollipop for chronic pain

Question 29

Parenteral morphine can be used to treat ________ in LVHF (may reduce preload and afterolad)

Answer 29

pulmonary edema