Opioids Flashcards
Differentiate between opiates and opioids
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
Describe the roles of the three opioid recepotors
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
Describe how opioids cause analgesia
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
Opioids have no _______, meaning increasing doses have increasing incremental effects
ceiling effect
Opioids are _____ by suppressing a specific center in the medulla
antitussive
The most significant adverse effect of opioids is ________
respiratory depression
List smooth muscle effects of opioids
Contraction of biliary tract smooth muscle, increased ureteral and bladder sphincter tone, decreased uterine tone, miosis
Opioids stimulate ______ release, leading to pruritis and orthostatic hypotension
histamine
List endocrine effects of opioids
Decreased libido, decreased production of LH–> amenorrhea, infertility, erectile dysfunction
Differentiate between tolerance, dependence, and addction
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
Describe the syndrome of opioid withdrawal
Nausea, diarrhea, coughing, rhinorrhea, diaphoresis, muscle pain and cramps (5-15 days)
Neonates: hypertonicity, tremor, restlessness, vomiting, fever (1-4 days)
______ is given to treat the autonomic hyperactivity syndromes in opioid withdrawal
clonidine
____ is a strong analgesic, is a strong agonist at mu receptors, and is the DOC for MI and cancer pain
Morphine
T/F: plasma concentration of morphine reliably predicts analgesic response
F: no predictable relationship between serum concentrations and analgesic response
Codeine has less _____ effect and more _____ effect compared to morphine
less analgesic, more antitussive
O-demethylation of codeine by ______ is essential for analgesic activity
CYP 2D6
Describe the mechanism of action of buprenorphine
partial agonist at mu receptors, antagonist at kappa receptors
exhibits ceiling effect in pharmacological effects
List uses for buprenorphine
Analgesia in opioid-naive people
Tx for opioid dependence (replacing methadone, can be prescribed in clinical office)
______ is a competitive antagonist with little or no agonistic activity at all opioid receptors
Naloxone
What is the objective of combining oxycodone with naloxone for PO delivery?
Discourages IV use- when used IV the naloxone will counteract the effects of oxycodone
Meperidine
mu and kappa agonist, 2nd line agent for acute pain but not for chronic use
tramadol
Synthetic analog of codeine; weak mu receptor agonist, also binds to NET and SERT
hydrocodone
antitussive and analgesic
methadone
full mu agonist with very long half life used for tx of outpatient dependence
oxycodone
strong agonist, can be combined with naloxone to discourage IV use
dextromethorphan
robitussin
antitussive, not analgesic. also a potent SERT inhibitor, could cause serotonin syndrome if used in combination with serotonergic drug
loperamide
used as antidiarrheal because does not cross BBB
fentanyl
Induction, maintenance of general anesthesia, transdermal patch or lollipop for chronic pain
Parenteral morphine can be used to treat ________ in LVHF (may reduce preload and afterolad)
pulmonary edema
