Opiods Mcq Flashcards
Which opioid receptor subtype is primarily responsible for analgesia and euphoria?
A. Delta (δ)
B. Sigma (σ)
C. Mu (μ)
D. Kappa (κ)
E. NMDA
C. Mu (μ)
Which endogenous opioid peptide has the highest affinity for delta receptors?
A. Endorphins
B. Enkephalins
C. Dynorphins
D. Nociceptin
E. Serotonin
B. Enkephalins
What is the main mechanism of opioid analgesia?
A. Activation of NMDA receptors
B. Inhibition of GABAergic neurons in the spinal cord
C. Inhibition of presynaptic calcium influx and postsynaptic potassium efflux
D. Inhibition of calcium influx and promotion of potassium efflux
E. Increased acetylcholine release in the thalamus
D. Inhibition of calcium influx and promotion of potassium efflux
Which of the following drugs is a partial μ-opioid agonist used in opioid addiction treatment?
A. Naloxone
B. Methadone
C. Buprenorphine
D. Fentanyl
E. Morphine
C. Buprenorphine
Which opioid is most likely to accumulate in patients with renal impairment and cause neurotoxicity?
A. Methadone
B. Morphine
C. Oxycodone
D. Fentanyl
E. Codeine
B. Morphine
What is the primary reason opioids cause constipation?
A. Inhibition of GI mucosal turnover
B. Blockade of histamine receptors in the gut
C. Suppression of parasympathetic tone
D. Activation of μ-receptors in the gastrointestinal tract
E. Increased secretion of mucus
D. Activation of μ-receptors in the gastrointestinal tract
Which of the following combinations increases the risk of serotonin syndrome when taken with tramadol?
A. Beta-blockers
B. Acetaminophen
C. SSRIs
D. Opioid antagonists
E. Antihistamines
C. SSRIs
Which opioid is commonly combined with acetaminophen and has a boxed warning for liver toxicity?
A. Morphine
B. Fentanyl
C. Hydrocodone
D. Methadone
E. Buprenorphine
C. Hydrocodone
What best explains why fentanyl is especially dangerous when misused?
A. It is a partial agonist that accumulates slowly
B. It is orally active and has high bioavailability
C. It is extremely potent and rapidly absorbed
D. It causes hallucinations at low doses
E. It cannot be detected in standard drug tests
C. It is extremely potent and rapidly absorbed
Which of the following is a long-acting opioid antagonist used for maintenance therapy?
A. Naloxone
B. Naltrexone
C. Tramadol
D. Methadone
E. Buprenorphine
B. Naltrexone
What is cross-tolerance in opioid pharmacology?
A. Developing resistance to all pain medications
B. Tolerance that develops between opioids acting on the same receptor
C. Resistance to opioids due to prior use of antidepressants
D. Inability to respond to any analgesic after long-term use
E. A reaction between opioids and benzodiazepines
B. Tolerance that develops between opioids acting on the same receptor
Which of the following best describes methadone’s dual mechanism of action?
A. μ-receptor partial agonist and NMDA agonist
B. Full μ-agonist and dopamine receptor blocker
C. μ-receptor agonist and NMDA receptor antagonist
D. GABA receptor agonist and serotonin inhibitor
E. Anticholinergic and antihistaminic
C. μ-receptor agonist and NMDA receptor antagonist
What distinguishes naloxone from naltrexone?
A. Naloxone is orally effective, naltrexone is not
B. Naloxone is long-acting, naltrexone is short-acting
C. Naloxone is used in emergency overdose; naltrexone is used for maintenance
D. Naloxone blocks κ receptors; naltrexone blocks μ receptors
E. Naloxone is only used for pain management
C. Naloxone is used in emergency overdose; naltrexone is used for maintenance
Which of the following opioids is NOT a prodrug?
A. Codeine
B. Tramadol
C. Hydrocodone
D. Morphine
E. Oxycodone
D. Morphine
What is the primary function of opioid agonists in the spinal cord dorsal horn?
A. Enhance glutamate release
B. Block acetylcholine-mediated EPSPs
C. Inhibit nociceptive afferent transmission
D. Stimulate serotonin release
E. Open calcium channels on interneurons
C. Inhibit nociceptive afferent transmission
A 27-year-old male is found unconscious with shallow breathing and pinpoint pupils. What is the immediate next step in management?
A. Administer naloxone
B. Start IV fluids and wait for toxicology
C. Give activated charcoal
D. Administer naltrexone
E. Monitor until spontaneous recovery
A. Administer naloxone
A 9-year-old child is prescribed codeine post-tonsillectomy. Within hours, she develops respiratory depression. What is the likely cause?
A. Codeine overdose
B. Antihistamine co-ingestion
C. CYP2D6 ultra-rapid metabolism
D. Allergy to morphine
E. Sepsis
C. CYP2D6 ultra-rapid metabolism
A dental patient with chronic pain is prescribed tramadol. Which comorbidity increases his risk for serotonin syndrome?
A. Diabetes
B. Hypertension
C. Depression on sertraline
D. Asthma
E. GERD
C. Depression on sertraline
A patient on chronic opioid therapy reports nausea and constipation but no pain relief. What is the best next step?
A. Stop opioids immediately
B. Add naloxone
C. Increase the dose
D. Switch to a different opioid
E. Add NSAIDs
D. Switch to a different opioid
A patient with severe dental pain is given oxycodone + acetaminophen. What should you warn the patient about?
A. Increased risk of kidney stones
B. Avoid alcohol to reduce liver toxicity
C. Opioids will reduce inflammation
D. They should take it with grapefruit juice
E. The combination will cause diarrhea
B. Avoid alcohol to reduce liver toxicity
An opioid-naïve patient is prescribed morphine for oral surgery. He returns with itching and hives. What’s the cause?
A. True opioid allergy
B. Serotonin syndrome
C. Histamine release
D. Acetaminophen reaction
E. Hypersensitivity to NSAIDs
C. Histamine release
A dental resident prescribes 30 tablets of hydrocodone/APAP for wisdom tooth removal. What’s the main public health concern?
A. Hepatotoxicity
B. Prolonged bleeding
C. Drug-seeking behavior
D. New persistent opioid use
E. Dental caries
D. New persistent opioid use
A 32-year-old patient with a heroin use disorder wants to quit. Which medication will reduce withdrawal symptoms and block euphoric effects?
A. Naloxone
B. Naltrexone
C. Buprenorphine
D. Methadone
E. Flumazenil
C. Buprenorphine
A patient with COPD and chronic back pain asks for opioids. What is your primary concern?
A. GI ulceration
B. Antidepressant interaction
C. Sedation and respiratory depression
D. Tachyphylaxis
E. Hepatotoxicity
C. Sedation and respiratory depression
