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Pain Mgmt RN study materials
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Pain Mgmt RN practice questions

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Question 1Pain Assessment and Pain Mechanisms

A patient reports pain that has continued for 6 months after the original injury healed. This pain is best classified as:

  1. Breakthrough pain
  2. Acute pain
  3. Chronic pain Correct answer.
  4. Referred pain

Explanation

Pain that persists beyond the expected period of tissue healing, conventionally 3 to 6 months, is classified as chronic pain. Chronic pain may continue in the absence of ongoing tissue damage and involves peripheral and central nervous system remodeling.

Question 2Pain Assessment and Pain Mechanisms

Which nerve fiber type transmits fast, sharp, well-localized pain impulses?

  1. A-delta fibers Correct answer.
  2. A-beta fibers
  3. C fibers
  4. Preganglionic B fibers

Explanation

A-delta fibers are thinly myelinated, conduct quickly, and carry the first, sharp, well-localized component of pain. C fibers are unmyelinated and produce a slower, dull, aching sensation.

Question 3Pain Assessment and Pain Mechanisms

A patient describes pain as burning, shooting, and tingling. These descriptors are most characteristic of which pain type?

  1. Burning, shooting, and tingling pain Correct answer.
  2. Cramping and intermittently colicky pain
  3. Dull, aching, and pressure-like pain
  4. Deep, poorly localized pain with sweating

Explanation

Burning, shooting, tingling, and electric-shock descriptors point to neuropathic pain arising from injury or dysfunction of the nervous system itself. Nociceptive pain from tissue injury is more often described as aching, throbbing, or pressure-like.

Question 4Pain Assessment and Pain Mechanisms

Place the four processes of nociception in the correct sequence.

  1. Perception, transduction, modulation, transmission
  2. Transmission, transduction, perception, modulation
  3. Transduction, perception, transmission, modulation
  4. Transduction, transmission, perception, modulation Correct answer.

Explanation

Nociception begins with transduction, in which a noxious stimulus is converted to an electrical impulse at the nociceptor. The impulse is then transmitted along afferent pathways to the spinal cord and brain, perceived in the cortex, and modified by descending modulatory pathways.

Question 5Pain Assessment and Pain Mechanisms

Pain threshold is best defined as:

  1. The level at which pain begins to interfere with sleep
  2. The length of time a painful stimulus can be applied
  3. The point at which a stimulus first becomes painful Correct answer.
  4. The greatest pain intensity a person can endure

Explanation

Pain threshold is the minimum intensity at which a stimulus is first perceived as painful, and it is relatively consistent across individuals. Pain tolerance, by contrast, is the maximum intensity a person is willing to endure and varies widely.

Question 6Pain Assessment and Pain Mechanisms

Which scale asks an adult patient to rate pain intensity on a 0-to-10 number line and requires the ability to comprehend the concept of numbers representing pain?

  1. PAINAD
  2. Wong-Baker FACES scale
  3. Critical-Care Pain Observation Tool
  4. Numeric Rating Scale Correct answer.

Explanation

The Numeric Rating Scale asks patients to assign a number from 0 to 10 to their pain and is validated for adults who can understand the abstract relationship between numbers and pain intensity. It is the most commonly used self-report tool in adult acute care.

Question 7Pain Assessment and Pain Mechanisms

The Wong-Baker FACES scale is most appropriate for which patient?

  1. A sedated patient receiving mechanical ventilation
  2. An adult with severe cognitive impairment who cannot point
  3. A 5-year-old child who can point to the face that matches their pain Correct answer.
  4. A patient with peripheral neuropathy who prefers numeric ratings

Explanation

The FACES scale presents a series of drawn faces and asks the patient to select the one matching their pain, making it suitable for young children who can point and understand simple face images. It relies on self-report and therefore requires a patient who is awake and able to indicate a choice.

Question 8Pain Assessment and Pain Mechanisms

Which tool is designed to assess pain in an adult who is intubated and unable to self-report?

  1. Numeric Rating Scale
  2. Visual Analog Scale
  3. Critical-Care Pain Observation Tool Correct answer.
  4. McGill Pain Questionnaire

Explanation

The Critical-Care Pain Observation Tool scores facial expression, body movements, muscle tension, and ventilator compliance or vocalization to estimate pain in patients who cannot communicate. Observational tools are required whenever self-report is not possible.

Question 9Pain Assessment and Pain Mechanisms

Which statement best guides pain assessment in a patient with advanced dementia?

  1. Vital signs alone reliably indicate pain intensity
  2. Behavioral tools should supplement self-report Correct answer.
  3. Pain should be assumed absent without a complaint
  4. Pain cannot be assessed once the patient stops reporting

Explanation

Patients with advanced dementia often cannot describe pain, so behavioral observation tools such as PAINAD are used alongside any self-report the patient can give. Untreated pain in this population frequently appears as agitation, guarding, or changes in breathing and vocalization.

Question 10Pain Assessment and Pain Mechanisms

According to the gate control theory, which nursing action would most likely reduce a patient's perception of pain?

  1. Rubbing the painful area or applying a cool compress Correct answer.
  2. Directing the patient to focus attention on the painful site
  3. Keeping the patient completely still and avoiding all touch
  4. Waiting until the pain becomes severe before intervening

Explanation

Gentle rubbing or a cool compress activates large-diameter A-beta sensory fibers, which inhibit transmission of pain signals in the dorsal horn and effectively close the gate. Nonpharmacologic measures such as massage, heat, cold, and distraction use this mechanism.

Question 11Pain Assessment and Pain Mechanisms

A patient reports severe pain when bed linens lightly brush against the skin. The nurse documents this finding as:

  1. Hyperalgesia
  2. Paresthesia
  3. Analgesia
  4. Allodynia Correct answer.

Explanation

Allodynia is pain produced by a stimulus that does not normally provoke pain, such as light touch or a bedsheet. It results from sensitization of central pain pathways and is common in neuropathic pain states.

Question 12Pain Assessment and Pain Mechanisms

Referred pain is best described as pain that:

  1. Arises from deep somatic structures and is usually well localized to that area
  2. Persists in a limb that has been surgically removed
  3. Is perceived in an area sharing the same spinal segment as its source Correct answer.
  4. Originates in a hollow organ and is described as cramping

Explanation

Referred pain is felt at a site distant from the tissue of origin because the visceral and somatic afferent fibers converge on the same spinal cord segment. A classic example is diaphragmatic irritation producing shoulder pain.

Question 13Pain Assessment and Pain Mechanisms

A patient reports burning and cramping in the left foot, which was amputated 2 months ago. The nurse recognizes this as:

  1. Referred pain
  2. Complex regional pain syndrome
  3. Phantom limb pain Correct answer.
  4. Residual limb nociceptive pain

Explanation

Phantom limb pain is pain perceived in a body part that has been amputated and is thought to arise from cortical reorganization and ectopic firing in severed nerves. It is distinct from residual limb pain, which occurs in the remaining tissue of the stump.

Question 14Pain Assessment and Pain Mechanisms

Which statement about vital signs as indicators of pain is most accurate?

  1. Heart rate rises in proportion to pain in every patient
  2. Vital signs often normalize in persistent pain Correct answer.
  3. Blood pressure is the single best measure of pain intensity
  4. Stable vital signs reliably rule out severe pain

Explanation

Sympathetic activation in acute pain raises heart rate, blood pressure, and respiratory rate, but these responses tend to return toward baseline in chronic or persistent pain. Vital signs therefore support but never substitute for self-report or behavioral assessment.

Question 15Pain Assessment and Pain Mechanisms

Which question best assesses the quality component of a pain history?

  1. When did the pain begin?
  2. Where is the pain located?
  3. What makes the pain better or worse?
  4. What does the pain feel like? Correct answer.

Explanation

Quality describes the sensory character of the pain, such as burning, aching, stabbing, or cramping, and helps distinguish nociceptive from neuropathic pain. Onset, location, and aggravating factors are separate assessment components.

Question 16Pain Assessment and Pain Mechanisms

Progressive amplification of dorsal horn neuron responses during repeated painful stimulation is termed:

  1. Descending inhibition
  2. Peripheral sensitization
  3. Wind-up Correct answer.
  4. Habituation

Explanation

Wind-up is the frequency-dependent increase in dorsal horn neuron responsiveness with repeated C-fiber input, primarily mediated by glutamate acting at NMDA receptors. It is a form of central sensitization that contributes to hyperalgesia.

Question 17Pain Assessment and Pain Mechanisms

The descending analgesic system reduces pain primarily by:

  1. Increasing sympathetic outflow to the skin
  2. Releasing endogenous opioids in the dorsal horn Correct answer.
  3. Blocking conduction along peripheral A-delta fibers
  4. Reducing cerebral blood flow to the thalamus

Explanation

Neurons from the periaqueductal gray and rostral ventromedial medulla project to the dorsal horn and release endogenous opioids, serotonin, and norepinephrine. These transmitters inhibit the presynaptic release of nociceptive neurotransmitters and reduce pain signaling.

Question 18Pain Assessment and Pain Mechanisms

Which neurotransmitter is released from primary afferent terminals in the dorsal horn to promote pain transmission?

  1. GABA
  2. Acetylcholine
  3. Substance P Correct answer.
  4. Dopamine

Explanation

Primary afferent nociceptors release glutamate and substance P in the dorsal horn, which excite second-order neurons and carry the pain signal upward. Substance P also contributes to neurogenic inflammation and central sensitization.

Question 19Pain Assessment and Pain Mechanisms

Which statement reflects current understanding of pain in neonates?

  1. Neonates mount stress responses but may show muted behavioral cues Correct answer.
  2. Neonates require higher analgesic doses than adults per kilogram
  3. Neonates do not perceive pain because myelin is incomplete
  4. Neonatal pain responses are purely reflexive and non-cortical

Explanation

Nociceptive pathways are functional by the second trimester, and neonates can demonstrate hormonal and autonomic stress responses to painful procedures. Because facial and behavioral cues may be muted or fluctuate, assessment combines behavioral tools with physiologic indicators.

Question 20Pain Assessment and Pain Mechanisms

The spinothalamic tract carries nociceptive information from the dorsal horn to which structure before relay to the cerebral cortex?

  1. Thalamus Correct answer.
  2. Medulla oblongata only
  3. Basal ganglia
  4. Cerebellum

Explanation

Second-order neurons decussate and ascend in the spinothalamic tract to the thalamus, which serves as the major relay station to the somatosensory cortex. Cortical processing of this input produces the conscious experience of pain.

Question 21Pain Assessment and Pain Mechanisms

Which set of findings is most consistent with acute, severe pain?

  1. Tachycardia, diaphoresis, and dilated pupils Correct answer.
  2. Normal pulse with increased appetite
  3. Bradycardia, dry skin, and pinpoint pupils
  4. Hypotension with warm, flushed extremities

Explanation

Acute pain triggers sympathetic activation, producing tachycardia, hypertension, diaphoresis, mydriasis, and tachypnea. These responses are adaptive in the short term but can increase myocardial workload and impair healing if pain persists.

Question 22Pain Assessment and Pain Mechanisms

Allodynia and hyperalgesia in chronic pain states are best explained by:

  1. Loss of peripheral nociceptors
  2. Central sensitization with amplified dorsal horn signaling Correct answer.
  3. Enhanced activity of descending inhibitory pathways
  4. Blockade of A-beta fiber input to the spinal cord

Explanation

Central sensitization increases the excitability of dorsal horn neurons so that normally innocuous input is perceived as painful and painful input is amplified. This maladaptive plasticity involves NMDA receptor activation, wind-up, and altered descending modulation.

Question 23Pain Assessment and Pain Mechanisms

Which tool measures the sensory and affective dimensions of pain using descriptive words selected by the patient?

  1. Numeric Rating Scale
  2. McGill Pain Questionnaire Correct answer.
  3. Faces Pain Scale-Revised
  4. Visual Analog Scale

Explanation

The McGill Pain Questionnaire asks patients to choose words from sensory, affective, and evaluative categories, yielding a multidimensional description of pain. Unidimensional scales measure only intensity.

Question 24Pain Assessment and Pain Mechanisms

A patient receiving long-acting morphine for cancer pain reports sudden episodes of severe pain that peak within minutes and occur several times daily. These episodes are best described as:

  1. End-of-dose failure
  2. Breakthrough pain Correct answer.
  3. Opioid-induced hyperalgesia
  4. Opioid tolerance

Explanation

Breakthrough pain is a transient exacerbation of pain in a patient whose baseline pain is otherwise controlled, often rapid in onset and severe. It may be incident pain triggered by activity or spontaneous, and is typically treated with short-acting analgesia.

Question 25Pain Assessment and Pain Mechanisms

Which characteristic best distinguishes visceral pain from somatic pain?

  1. It is always described as burning or electric in nature
  2. It resolves within minutes of the stimulus being removed
  3. It is poorly localized and often accompanied by autonomic symptoms Correct answer.
  4. It is sharp and precisely localized to the site of injury

Explanation

Visceral pain from hollow organs is diffuse and poorly localized because visceral afferents are sparse, and it frequently triggers autonomic responses such as nausea, sweating, pallor, and blood pressure changes. Somatic pain is generally well localized because somatic innervation is dense.

Question 26Pain Assessment and Pain Mechanisms

Which statement best reflects the current definition of pain?

  1. An unpleasant sensory and emotional experience linked to actual or potential tissue damage Correct answer.
  2. A purely physical sensation that is proportional to the amount of tissue damage present
  3. A spinal reflex arc that protects the body from further injury without cortical input
  4. A psychological reaction that occurs only after tissue damage has been confirmed by testing

Explanation

Pain is defined by the International Association for the Study of Pain as an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage. The definition explicitly notes that pain is not proportional to tissue damage and can occur without a documented injury.

Question 27Pain Assessment and Pain Mechanisms

Which description defines chronic pain?

  1. Pain that is reported only during movement and is absent when the patient is resting quietly
  2. Pain that persists beyond the usual healing period, typically past three months Correct answer.
  3. Pain that is caused by a defined noxious stimulus and disappears when the stimulus is removed
  4. Pain that begins suddenly and resolves completely once the underlying tissue has healed

Explanation

Chronic pain is defined by duration beyond the expected healing period, commonly three months or longer. It may persist after tissues have healed and often involves nervous system changes rather than ongoing noxious input.

Question 28Pain Assessment and Pain Mechanisms

A patient describes pain as burning and shooting, with tingling in the toes. The nurse recognizes these descriptors as most consistent with which type of pain?

  1. Somatic nociceptive pain
  2. Neuropathic pain Correct answer.
  3. Referred somatic pain
  4. Visceral nociceptive pain

Explanation

Burning, shooting, electric, and tingling descriptors point to nerve injury or dysfunction, the hallmark of neuropathic pain. Nociceptive pain is more often described as aching, throbbing, or pressure-like.

Question 29Pain Assessment and Pain Mechanisms

Which term is defined as the least intensity of a stimulus at which a person first perceives pain?

  1. Pain tolerance
  2. Allodynia
  3. Hyperalgesia
  4. Pain threshold Correct answer.

Explanation

Pain threshold is the lowest stimulus intensity at which pain is first perceived. It is relatively consistent across individuals, unlike tolerance.

Question 30Pain Assessment and Pain Mechanisms

A patient jerks the hand away immediately after touching a hot pan and then, seconds later, reports a dull aching pain. Which mechanism best explains this sequence?

  1. C fibers triggered the fast withdrawal, and A-beta fibers produced the delayed aching pain
  2. A-delta fibers triggered the fast withdrawal, and slower C fibers produced the delayed aching pain Correct answer.
  3. Sympathetic efferent fibers carried both the withdrawal response and the delayed aching sensation
  4. A-beta fibers carried both the withdrawal response and the delayed aching sensation to the brain

Explanation

A-delta fibers are thinly myelinated and conduct quickly, producing the sharp first pain that triggers withdrawal. Unmyelinated C fibers conduct slowly and produce the delayed dull, aching second pain.

Question 31Pain Assessment and Pain Mechanisms

A topical local anesthetic applied to intact skin reduces pain by blocking sodium channels in peripheral nerve endings. Which nociceptive process does this primarily interrupt?

  1. Transduction Correct answer.
  2. Perception
  3. Transmission
  4. Modulation

Explanation

Transduction is the conversion of a noxious stimulus into an electrical signal at the peripheral nerve ending, a step dependent on sodium channel activity. Blocking those channels prevents the action potential from being generated.

Question 32Pain Assessment and Pain Mechanisms

A patient with acute pain receives intravenous morphine. When should the nurse reassess the patient's pain?

  1. After 2 hours
  2. Within 5 minutes
  3. At the end of the shift
  4. In 15 to 30 minutes Correct answer.

Explanation

After an intravenous opioid, peak effect typically occurs within about 15 to 30 minutes, so reassessment at that point reflects the drug's full impact. Waiting longer delays needed adjustments.

Question 33Pain Assessment and Pain Mechanisms

An older adult with delirium grimaces and guards the abdomen but cannot answer questions about pain. Which approach is most appropriate?

  1. Use a behavioral tool such as PAINAD and observe guarding and facial expression Correct answer.
  2. Defer pain assessment until the delirium has resolved
  3. Document that the patient denies pain and reassess at the next shift
  4. Ask the patient's adult child to rate the pain for the patient on a 0-to-10 numeric rating scale

Explanation

Patients with delirium may be unable to provide a reliable self-report, so validated behavioral tools that score facial expression, body movement, and guarding are used. Behavioral signs should be treated and then reassessed.

Question 34Pain Assessment and Pain Mechanisms

A patient who speaks only Spanish reports pain after surgery. Which approach is best for obtaining a pain assessment?

  1. Ask the patient's adult child to interpret during the assessment so that the process moves quickly
  2. Ask a bilingual staff member from another unit to translate at the bedside
  3. Use a trained medical interpreter and give the pain scale in the patient's language Correct answer.
  4. Rely on gestures and facial expressions since pain is a universal experience

Explanation

Accurate assessment requires a trained medical interpreter and a scale validated in the patient's preferred language. Untrained ad hoc interpreters risk errors and confidentiality breaches.

Question 35Pain Assessment and Pain Mechanisms

Which statement best distinguishes nociception from pain?

  1. Nociception is neural processing of noxious input; pain is the subjective experience Correct answer.
  2. Nociception and pain are interchangeable terms for the same neural event
  3. Nociception always produces the experience of pain once the signal reaches the cerebral cortex
  4. Pain occurs only when nociceptors are activated by tissue injury

Explanation

Nociception is the physiological processing of noxious stimuli from transduction through transmission to the brain. Pain is the subjective, multidimensional experience that can be modulated and can occur without measurable nociceptive input.

Question 36Pain Assessment and Pain Mechanisms

A patient receiving escalating doses of intravenous opioids for cancer pain reports increasingly diffuse pain and a falling pain threshold despite the higher doses. Which explanation should the nurse consider?

  1. Acute opioid toxicity
  2. Opioid tolerance
  3. Opioid withdrawal
  4. Opioid-induced hyperalgesia Correct answer.

Explanation

Escalating opioid doses accompanied by worsening, more diffuse pain and reduced pain thresholds suggest opioid-induced hyperalgesia, a paradoxical sensitization. The response is to reassess the regimen rather than continue escalating.

Question 37Pain Assessment and Pain Mechanisms

Which factor is most likely to reduce a patient's tolerance for pain?

  1. Anxiety and fear about the meaning of the pain Correct answer.
  2. A sense of control over the situation
  3. Engagement in an absorbing activity
  4. Adequate sleep the night before

Explanation

Anxiety, fear, fatigue, and a sense of helplessness lower pain tolerance, while sleep, control, and distraction raise it. Psychosocial context is a strong determinant of the pain experience.

Question 38Pain Assessment and Pain Mechanisms

Which brain regions are most associated with the affective-motivational dimension of pain?

  1. Dorsal column nuclei and medial lemniscus
  2. Primary somatosensory cortex and ventrobasal thalamus
  3. Cerebellum and basal ganglia
  4. Anterior cingulate cortex and insula Correct answer.

Explanation

The affective-motivational dimension of pain is linked to the anterior cingulate cortex and insula, which underlie the unpleasantness of pain. The somatosensory cortex subserves the sensory-discriminative dimension such as location and intensity.

Question 39Pain Assessment and Pain Mechanisms

Six weeks after a wrist fracture, a patient has severe burning pain, swelling, and skin color and temperature changes in the hand that are far out of proportion to the original injury. Which condition is most consistent with these findings?

  1. Complex regional pain syndrome Correct answer.
  2. Compression of the median nerve in the carpal tunnel
  3. Expected residual discomfort from normal fracture healing
  4. Acute compartment syndrome with arterial compromise

Explanation

Severe burning pain, swelling, and vasomotor skin changes disproportionate to the injury, developing weeks after a fracture, are characteristic of complex regional pain syndrome. Early recognition matters because treatment is more effective when started promptly.

Question 40Pain Assessment and Pain Mechanisms

A preoperative analgesic regimen is administered before the surgical incision is made. Which rationale best supports this practice?

  1. It blocks nociceptive input before nervous system sensitization can develop Correct answer.
  2. It prevents the patient from forming explicit memories of the surgical procedure
  3. It reduces the total dose of inhalation anesthetic required during the operation
  4. It removes the need for pain assessment in the recovery period

Explanation

Preemptive analgesia is given before the painful stimulus to prevent the barrage of nociceptive input that leads to peripheral and central sensitization. This can reduce subsequent pain intensity and analgesic requirements.

Question 41Pharmacologic Pain Management and Analgesic Safety

According to FDA-approved labeling, what is the maximum total daily dose of acetaminophen for a healthy adult without hepatic impairment or regular alcohol use?

  1. 4,000 mg Correct answer.
  2. 3,000 mg
  3. 2,000 mg
  4. 6,000 mg

Explanation

Labeled adult maximum is 4,000 mg per 24 hours from all sources, including combination products. Toxicity is dose-dependent and mediated by the reactive metabolite NAPQI once glucuronidation and sulfation pathways are saturated. Many institutions adopt a stricter 3,000 mg ceiling, but that is a local safety practice rather than the labeled maximum.

Question 42Pharmacologic Pain Management and Analgesic Safety

Which medication, co-prescribed with a nonselective NSAID, reduces gastric ulcer risk by replacing prostaglandins depleted by COX inhibition?

  1. Dicyclomine
  2. Misoprostol Correct answer.
  3. Ondansetron
  4. Sucralfate

Explanation

Nonselective NSAIDs block COX-1 in the gastric mucosa, depleting protective prostaglandins and impairing mucus and bicarbonate secretion. Misoprostol is a prostaglandin E1 analog that restores that protection and has demonstrated reduction in NSAID-related ulcers. Proton pump inhibitors are also used clinically, but they work by suppressing acid rather than by replacing prostaglandins.

Question 43Pharmacologic Pain Management and Analgesic Safety

A patient taking scheduled oxycodone for cancer pain reports no bowel movement in four days and abdominal fullness. Which intervention is most appropriate?

  1. Increase the oxycodone dose to improve comfort
  2. Start a scheduled stimulant laxative such as senna Correct answer.
  3. Withhold all opioids until a bowel movement occurs
  4. Add a bulk-forming fiber laxative as the sole agent

Explanation

Opioids slow colonic transit through mu-receptor activity in the gut, so prophylactic stimulant laxatives are recommended for patients on chronic opioid therapy. Bulk-forming agents alone can worsen obstruction-type symptoms when transit is already slow and fluid intake is limited. Opioid doses should be adjusted for analgesia, not used as a bowel regimen, and analgesia should not be withheld.

Question 44Pharmacologic Pain Management and Analgesic Safety

Naloxone reverses opioid-induced respiratory depression through which mechanism?

  1. Inhibiting hepatic glucuronidation of opioids
  2. Releasing endogenous opioids from the adrenal medulla
  3. Competitive antagonism at mu-opioid receptors Correct answer.
  4. Increasing mu-receptor sensitivity to endogenous opioids

Explanation

Naloxone is a pure opioid antagonist with high affinity for mu, kappa, and delta receptors, displacing opioid agonists and reversing sedation and hypoventilation. It has no agonist activity of its own and does not alter opioid metabolism or elimination. Because its duration is shorter than many opioids, repeat dosing or an infusion may be required.

Question 45Pharmacologic Pain Management and Analgesic Safety

A patient with stage 4 chronic kidney disease needs a long-acting opioid for cancer pain. Which agent is least likely to accumulate active metabolites?

  1. Morphine
  2. Fentanyl Correct answer.
  3. Codeine
  4. Meperidine

Explanation

Fentanyl undergoes hepatic metabolism to inactive metabolites, so it is the preferred opioid in significant renal impairment. Morphine, codeine, and meperidine all generate renally cleared metabolites that produce neurotoxicity or prolonged sedation when clearance falls.

Question 46Pharmacologic Pain Management and Analgesic Safety

Which opioid should be avoided in a patient taking a monoamine oxidase inhibitor because of serotonin syndrome risk and accumulation of a neurotoxic metabolite?

  1. Morphine
  2. Hydromorphone
  3. Meperidine Correct answer.
  4. Oxycodone

Explanation

Meperidine inhibits serotonin reuptake and, combined with MAOIs, can precipitate serotonin syndrome with agitation, hyperthermia, and rigidity. Its metabolite normeperidine has CNS excitatory effects, producing myoclonus and seizures, especially with repeated dosing or renal impairment.

Question 47Pharmacologic Pain Management and Analgesic Safety

A breastfed infant becomes profoundly sedated after the mother takes codeine. Which mechanism best explains this?

  1. Reduced renal clearance of unchanged codeine
  2. Ultrarapid CYP2D6 metabolism producing excess morphine Correct answer.
  3. Absence of mu-opioid receptors in the infant
  4. Slow CYP3A4 metabolism causing codeine accumulation

Explanation

Codeine is a prodrug requiring CYP2D6 conversion to morphine for analgesia. Ultrarapid metabolizers convert codeine rapidly and generate high morphine concentrations that pass into breast milk and can cause infant sedation and respiratory depression. This is why codeine is avoided in breastfeeding mothers and in children after tonsillectomy.

Question 48Pharmacologic Pain Management and Analgesic Safety

Which patient should avoid tramadol?

  1. A 30-year-old with migraine and no other medications
  2. A 60-year-old with knee osteoarthritis
  3. A 45-year-old with hypertension taking amlodipine
  4. A 38-year-old taking fluoxetine with a seizure history Correct answer.

Explanation

Tramadol inhibits serotonin and norepinephrine reuptake and lowers the seizure threshold, so it is avoided in patients with seizure disorders and used cautiously with SSRIs because of additive serotonergic effects. Fluoxetine also inhibits CYP2D6, reducing conversion of tramadol to its active metabolite.

Question 49Pharmacologic Pain Management and Analgesic Safety

Children and teenagers recovering from a viral illness should avoid aspirin because of which associated condition?

  1. Nephrogenic diabetes insipidus
  2. Acute dystonic reaction
  3. Reye syndrome Correct answer.
  4. Stevens-Johnson syndrome

Explanation

Salicylate use during a viral illness in children is epidemiologically linked to Reye syndrome, an acute encephalopathy with fatty liver and cerebral edema. The mechanism is thought to involve mitochondrial injury, particularly when viral illness alters fatty acid oxidation. Other analgesics such as acetaminophen or ibuprofen are preferred in this age group.

Question 50Pharmacologic Pain Management and Analgesic Safety

When ketorolac is used for acute pain, the combined duration of therapy by all routes should generally not exceed how many days?

  1. 5 days Correct answer.
  2. 10 days
  3. 2 days
  4. 14 days

Explanation

Ketorolac labeling limits combined intramuscular, intravenous, and oral therapy to a total of 5 days because the risk of GI bleeding, renal injury, and platelet dysfunction rises steeply with longer exposure. Patients should transition to a less toxic analgesic after that window.