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ABPN Pain Medicine study materials
ABPN Pain Medicine study resources

ABPN Pain Medicine practice questions

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Question 1Pain Assessment, Diagnosis, and Clinical Evaluation

Neuropathic pain is best defined as pain caused by which process?

  1. Inflammation of musculoskeletal structures after overuse
  2. Emotional distress without identifiable tissue injury
  3. A lesion or disease affecting the somatosensory nervous system Correct answer.
  4. Activation of peripheral nociceptors by tissue injury

Explanation

The accepted definition requires a lesion or disease of the somatosensory nervous system, not merely pain in a neuroanatomic distribution. Nociceptive pain arises from actual or threatened damage to non-neural tissue and is due to activation of nociceptors. This distinction guides the use of neuropathic pain screening tools and sensory examination.

Question 2Pain Assessment, Diagnosis, and Clinical Evaluation

On a 0-to-10 numeric rating scale, which score range is conventionally labeled severe pain?

  1. 0 to 1
  2. 7 to 10 Correct answer.
  3. 1 to 3
  4. 4 to 6

Explanation

The numeric rating scale is anchored at 0 for no pain and 10 for the worst pain imaginable. Mild pain is usually 1 to 3, moderate pain 4 to 6, and severe pain 7 to 10. These cut points aid communication but do not replace assessment of function and context.

Question 3Pain Assessment, Diagnosis, and Clinical Evaluation

A visual analog scale for pain typically consists of which format?

  1. A 5-point verbal descriptor list read aloud
  2. A 10-item questionnaire about pain quality
  3. A 100-mm line anchored at each end by no pain and worst pain imaginable Correct answer.
  4. A grid of faces representing different pain intensities

Explanation

The visual analog scale is usually a 100-mm horizontal or vertical line with anchors such as no pain and worst pain imaginable. The patient marks intensity and the distance from the no-pain end is measured. It provides a continuous score but requires adequate vision and motor ability.

Question 4Pain Assessment, Diagnosis, and Clinical Evaluation

On the McGill Pain Questionnaire, descriptors such as fearful and punishing-cruel belong to which dimension?

  1. Evaluative
  2. Miscellaneous
  3. Affective Correct answer.
  4. Sensory

Explanation

The McGill Pain Questionnaire groups descriptors into sensory, affective, evaluative, and miscellaneous dimensions. Affective descriptors capture the emotional suffering associated with pain, such as fearful and punishing-cruel. Sensory words describe quality, while evaluative words describe overall intensity.

Question 5Pain Assessment, Diagnosis, and Clinical Evaluation

The DN4 questionnaire uses how many items and what cutoff to suggest neuropathic pain?

  1. 10 items; a score of 4 or more Correct answer.
  2. 9 items; a score of 19 or more
  3. 7 items; a score of 3 or more
  4. 5 items; a score of 2 or more

Explanation

The DN4 has 7 sensory descriptor items and 3 bedside examination items, for 10 total. A score of 4 or more out of 10 suggests neuropathic pain. It is a screening instrument and does not replace clinical diagnosis.

Question 6Pain Assessment, Diagnosis, and Clinical Evaluation

On the PainDETECT questionnaire, which total score is conventionally used to indicate a likely neuropathic pain component?

  1. A score of 30 or greater
  2. A score of 19 or greater Correct answer.
  3. A score of 10 or greater
  4. A score of 4 or greater

Explanation

PainDETECT scores range from 0 to 38. Scores of 12 or less suggest an unlikely neuropathic component, 13 to 18 are uncertain, and 19 or greater suggest a likely neuropathic component. The questionnaire includes pain quality, spatial and temporal pattern, and radiation.

Question 7Pain Assessment, Diagnosis, and Clinical Evaluation

Allodynia is defined as which phenomenon?

  1. An increased pain response to a normally painful stimulus
  2. Pain felt in a region remote from its source
  3. A brief painful after-sensation following a stimulus
  4. Pain evoked by a stimulus that is normally not painful Correct answer.

Explanation

Allodynia is pain produced by a stimulus that is normally non-noxious, such as light touch or brushing. It reflects altered sensory processing and is common in neuropathic pain states. It is distinct from hyperalgesia, which is an exaggerated response to a normally painful stimulus.

Question 8Pain Assessment, Diagnosis, and Clinical Evaluation

Hyperalgesia refers to which finding on sensory examination?

  1. Increased pain from a stimulus that is normally painful Correct answer.
  2. Loss of pain sensation in a dermatome
  3. Pain produced by light touch
  4. A tingling sensation without stimulation

Explanation

Hyperalgesia is an exaggerated pain response to a stimulus that is normally painful, such as pinprick. It may occur at the site of injury as primary hyperalgesia or in surrounding tissue as secondary hyperalgesia. It indicates altered nociceptive processing.

Question 9Pain Assessment, Diagnosis, and Clinical Evaluation

During evaluation of a patient with low back pain, the examiner notes superficial widespread tenderness, pain simulation with axial loading, and inconsistent straight-leg raising. These findings are most consistent with which interpretation?

  1. Ankylosing spondylitis with sacroiliac inflammation
  2. Nonorganic Waddell signs, which should prompt biopsychosocial assessment rather than dismissal Correct answer.
  3. Cauda equina syndrome until proven otherwise
  4. Definite lumbar radiculopathy requiring immediate surgery

Explanation

Waddell signs are a set of nonorganic physical findings; three or more raise concern for psychosocial distress and illness behavior but do not mean the pain is feigned. They should prompt broader biopsychosocial evaluation rather than dismissal. They are not diagnostic of structural disease.

Question 10Pain Assessment, Diagnosis, and Clinical Evaluation

The PAINAD scale for assessing pain in advanced dementia includes which set of items?

  1. Breathing, vocalization, facial expression, body language, and consolability Correct answer.
  2. Pain location, quality, intensity, and duration
  3. Crying, oxygen requirement, vital signs, expression, and sleeplessness
  4. Face, legs, activity, cry, and consolability

Explanation

PAINAD has five observational items: breathing independent of vocalization, negative vocalization, facial expression, body language, and consolability. It is scored from 0 to 10 and is used when self-report is unreliable. It is designed for patients with advanced dementia.

Question 11Pain Assessment, Diagnosis, and Clinical Evaluation

The FLACC scale is designed primarily for which purpose?

  1. Measuring pain-related fear in children
  2. Observational pain assessment in young children who cannot self-report Correct answer.
  3. Quantifying pain intensity using a 100-mm line
  4. Diagnosing neuropathic pain in adults

Explanation

FLACC stands for Face, Legs, Activity, Cry, and Consolability; each item is scored 0 to 2 for a total of 0 to 10. It is an observational tool for young or nonverbal children. It assesses pain behavior rather than diagnosing pain mechanisms.

Question 12Pain Assessment, Diagnosis, and Clinical Evaluation

A 2-day-old postoperative neonate is assessed with the CRIES scale. Which item set correctly matches the acronym?

  1. Crying, requires oxygen, increased vital signs, expression, sleeplessness Correct answer.
  2. Color, respiration, interaction, expression, sleep
  3. Crying, response, immobility, expression, sedation
  4. Consolability, respiration, irritability, expression, sleep

Explanation

CRIES is a neonatal postoperative pain scale: Crying, Requires oxygen for saturation above 95%, Increased vital signs, Expression, and Sleeplessness. Each item is scored 0 to 2, giving a total of 0 to 10. It was developed for preterm and term neonates.

Question 13Pain Assessment, Diagnosis, and Clinical Evaluation

Which feature in a patient with new low back pain is a red flag that warrants urgent further evaluation?

  1. Bilateral paraspinal muscle tenderness
  2. Pain that began after lifting a heavy box
  3. A history of cancer with new night pain and unexplained weight loss Correct answer.
  4. Pain that improves with gentle movement

Explanation

Red flags include a history of cancer, unexplained weight loss, night pain, fever, trauma, age over 50 with new pain, and neurologic deficits. These features raise concern for infection, malignancy, fracture, or cauda equina syndrome. They warrant timely investigation rather than routine conservative management alone.

Question 14Pain Assessment, Diagnosis, and Clinical Evaluation

A patient has persistent disproportionate pain after a wrist fracture. According to the Budapest criteria, which combination is required to make a clinical diagnosis of complex regional pain syndrome?

  1. At least one symptom in three of four categories and at least one sign in two or more categories Correct answer.
  2. At least two symptoms in two categories and no need for signs
  3. Positive bone scan and response to sympathetic block
  4. Symptoms in all four categories and signs in all four categories

Explanation

The Budapest criteria require continuing pain disproportionate to the inciting event, at least one symptom in three of four categories, and at least one sign in two or more categories, with no better diagnosis. The four categories are sensory, vasomotor, sudomotor or edema, and motor or trophic. Symptoms alone are insufficient.

Question 15Pain Assessment, Diagnosis, and Clinical Evaluation

Under the 2016 fibromyalgia criteria, which combination satisfies the widespread pain and symptom severity requirements?

  1. WPI at least 5 and SSS at least 7 only
  2. WPI at least 7 and SSS at least 5, or WPI 4 to 6 and SSS at least 9 Correct answer.
  3. WPI at least 10 and SSS at least 1
  4. WPI at least 3 and SSS at least 3

Explanation

The 2016 revision uses a WPI of 7 or more and an SSS of 5 or more, or a WPI of 4 to 6 and an SSS of 9 or more. Symptoms must be present for at least 3 months, and no other diagnosis should explain them. The WPI counts painful body regions, while the SSS rates fatigue, unrefreshing sleep, and cognitive symptoms.

Question 16Pain Assessment, Diagnosis, and Clinical Evaluation

A myofascial trigger point is best characterized by which finding?

  1. A focal hyperirritable spot in a taut muscle band that reproduces referred pain Correct answer.
  2. A dermatomal band of allodynia
  3. A palpable nerve trunk with a Tinel sign
  4. A symmetric tender point at a tendon insertion in fibromyalgia

Explanation

Trigger points are focal, hyperirritable spots within taut muscle bands; compression may produce local and referred pain and a local twitch response. They differ from fibromyalgia tender points, which are not associated with taut bands. Trigger points are a clinical finding, not a nerve entrapment sign.

Question 17Pain Assessment, Diagnosis, and Clinical Evaluation

Referred pain from visceral structures is best explained by which mechanism?

  1. Loss of descending inhibition after cortical injury
  2. Compression of the dorsal root ganglion by a disc herniation
  3. Convergence of visceral and somatic afferents onto the same dorsal horn neurons Correct answer.
  4. Direct spread of inflammation along a peripheral nerve

Explanation

Visceral afferents converge with somatic afferents on second-order dorsal horn neurons, and the brain may misattribute the source to the more familiar somatic dermatome. This is known as the convergence-projection concept. It explains why visceral pain is often felt in characteristic cutaneous regions.

Question 18Pain Assessment, Diagnosis, and Clinical Evaluation

Phantom limb pain is best described as which phenomenon?

  1. Pain in the residual limb caused by neuroma formation
  2. Nonpainful awareness of the absent limb
  3. Pain perceived in the absent body part after amputation Correct answer.
  4. Pain from an ill-fitting prosthesis

Explanation

Phantom limb pain is pain referred to the amputated body part. It differs from phantom sensation, which is a nonpainful awareness that the limb is still present. Mechanisms include peripheral and central nervous system reorganization.

Question 19Pain Assessment, Diagnosis, and Clinical Evaluation

Which statement correctly distinguishes pain threshold from pain tolerance?

  1. Threshold and tolerance are interchangeable terms in psychophysics
  2. Threshold is the maximum pain a person can endure, while tolerance is the first perception of pain
  3. Threshold is measured only by questionnaire, while tolerance is measured by reflex
  4. Threshold is the lowest stimulus intensity perceived as painful, while tolerance is the greatest intensity a person is willing to endure Correct answer.

Explanation

Pain threshold is the minimum stimulus intensity at which a stimulus is perceived as painful. Pain tolerance is the maximum intensity a person is willing to endure. Tolerance is influenced more by psychological and contextual factors than threshold is.

Question 20Pain Assessment, Diagnosis, and Clinical Evaluation

In a psychophysical experiment, a subject's pain rating to a fixed heat stimulus decreases when the same hand is immersed in ice water. This finding best illustrates which process?

  1. Peripheral sensitization of nociceptors
  2. Conditioned pain modulation Correct answer.
  3. Wind-up of dorsal horn neurons
  4. Temporal summation of C-fiber input

Explanation

Conditioned pain modulation is a decrease in response to a test stimulus when a noxious conditioning stimulus is applied elsewhere. It is a human correlate of endogenous descending inhibition. Reduced conditioned pain modulation is associated with several chronic pain states.

Question 21Pain Assessment, Diagnosis, and Clinical Evaluation

Which pathway is most directly involved in descending inhibition of nociceptive transmission?

  1. Spinothalamic tract to primary somatosensory cortex
  2. Dorsal root ganglion to ventral posterolateral thalamus
  3. Sympathetic chain to peripheral nociceptors
  4. Periaqueductal gray to rostral ventromedial medulla to dorsal horn Correct answer.

Explanation

The descending inhibitory system includes the periaqueductal gray, the rostral ventromedial medulla, and dorsal horn interneurons. It uses serotonin, norepinephrine, and endogenous opioids to modulate ascending nociceptive input. This pathway is a key target of analgesic and stress-related pain modulation.

Question 22Pain Assessment, Diagnosis, and Clinical Evaluation

An older adult with advanced Alzheimer disease and limited verbal communication appears agitated during repositioning. Which approach is most appropriate for assessing pain?

  1. Use a validated observational scale such as PAINAD and gather caregiver input Correct answer.
  2. Rely only on a 0-to-10 numeric rating scale
  3. Assume pain is absent because the patient cannot report it
  4. Obtain a routine serum pain panel

Explanation

When self-report is unreliable, validated observational tools plus caregiver knowledge and attention to reversible causes are recommended. Agitation may be a pain behavior in a patient with advanced dementia. A numeric rating scale is not valid when the patient cannot reliably use it.

Question 23Pain Assessment, Diagnosis, and Clinical Evaluation

Before initiating long-term opioid therapy for chronic pain, which approach to substance use risk is most appropriate?

  1. Avoid screening because it may damage the therapeutic relationship
  2. Use a validated screening tool such as the DAST-10 or AUDIT and review prescription monitoring data Correct answer.
  3. Order a urine drug screen and proceed only if it is negative
  4. Ask a single yes-or-no question about street drug use

Explanation

Validated screening instruments and prescription monitoring data help stratify risk and guide monitoring. A single question or one urine test is insufficient for a comprehensive risk assessment. Screening should be nonjudgmental and paired with risk mitigation.

Question 24Pain Assessment, Diagnosis, and Clinical Evaluation

Pain catastrophizing is characterized by which cognitive pattern?

  1. Deliberate distraction from pain during activity
  2. Belief that activity should be avoided until pain resolves
  3. Rumination, magnification, and helplessness about pain Correct answer.
  4. Excessive focus on physical symptoms with repeated body checking

Explanation

Catastrophizing involves rumination, magnification, and helplessness regarding pain. It is associated with greater pain intensity, disability, and poorer treatment response. It is a common target for cognitive-behavioral therapy.

Question 25Pain Assessment, Diagnosis, and Clinical Evaluation

In the grading system for neuropathic pain, which finding is required for the category confirmed neuropathic pain?

  1. Pain with a burning quality in a stocking distribution
  2. A diagnostic test confirming a lesion or disease of the somatosensory system Correct answer.
  3. A positive response to a trial of gabapentin
  4. A PainDETECT score of 19 or higher

Explanation

The grading system moves from possible neuropathic pain, based on history and distribution, to probable neuropathic pain with clinical signs, to confirmed neuropathic pain with a diagnostic test confirming the lesion or disease. Screening questionnaires and treatment response do not confirm the diagnosis. Confirmation requires objective evidence of a somatosensory lesion or disease.

Question 26Pain Assessment, Diagnosis, and Clinical Evaluation

A patient describes pain that feels like burning, electric shocks, and shooting jabs. Which descriptor pattern is this most consistent with?

  1. Cramping, colicky, and poorly localized
  2. Dull, aching, and pressure-like
  3. Throbbing and relieved by elevation
  4. Burning, electric-shock-like, and shooting Correct answer.

Explanation

Neuropathic pain results from a lesion or disease of the somatosensory nervous system, and its hallmark descriptors are burning, lancinating, electric-shock-like, and shooting sensations, often with numbness or tingling. Somatic nociceptive pain is typically dull, aching, and pressure-like, while visceral pain is more often cramping and poorly localized. Vascular pain tends to throb and may relate to position or perfusion.

Question 27Pain Assessment, Diagnosis, and Clinical Evaluation

A 6-year-old child with a painful forearm injury needs to self-report pain intensity. Which instrument is designed for this purpose?

  1. PAINAD
  2. Faces Pain Scale-Revised Correct answer.
  3. Critical-Care Pain Observation Tool
  4. Numeric Rating Scale (0-10)

Explanation

The Faces Pain Scale-Revised uses six line-drawn faces and was developed and validated for children roughly 4 years and older who can match a face to how they feel. Observational tools such as PAINAD and the Critical-Care Pain Observation Tool are used when a patient cannot self-report, and the numeric rating scale requires abstract number concepts that most young children have not yet mastered.

Question 28Pain Assessment, Diagnosis, and Clinical Evaluation

Which instrument asks the patient to select words from grouped descriptor lists and yields separate sensory, affective, evaluative, and miscellaneous scores?

  1. McGill Pain Questionnaire Correct answer.
  2. Pain Catastrophizing Scale
  3. Brief Pain Inventory
  4. Oswestry Disability Index

Explanation

The McGill Pain Questionnaire is a multidimensional verbal descriptor instrument in which patients choose qualifying words from numbered groups, generating sensory, affective, evaluative, and miscellaneous subscale scores plus a total pain rating index. The other instruments quantify interference, catastrophic thinking, or functional disability rather than pain quality.

Question 29Pain Assessment, Diagnosis, and Clinical Evaluation

The DN4 questionnaire is used to screen for neuropathic pain. Which total score supports that classification?

  1. At least 3 of 10 points
  2. At least 2 of 10 points
  3. At least 4 of 10 points Correct answer.
  4. At least 6 of 10 points

Explanation

The DN4 consists of 7 interview items on pain quality and irradiation plus 3 bedside examination items (brush allodynia, pinprick hypoalgesia, and pain on light touch), for a maximum of 10 points. A total of 4 or more is the established cutoff for neuropathic pain, with reported sensitivity and specificity near 80%.

Question 30Pain Assessment, Diagnosis, and Clinical Evaluation

A patient has neck pain radiating into the arm with tingling in the index finger. Which bedside maneuver, when it reproduces the arm symptoms, most supports cervical nerve root compression?

  1. Adson test
  2. Straight leg raise
  3. Spurling test Correct answer.
  4. Phalen test

Explanation

The Spurling test combines cervical extension, ipsilateral rotation, and axial compression, narrowing the ipsilateral intervertebral foramen and provoking radicular pain when a nerve root is compressed. It is highly specific but relatively insensitive, so a positive result is more informative than a negative one.

Question 31Pain Assessment, Diagnosis, and Clinical Evaluation

An older adult reports bilateral buttock and thigh aching that develops after walking a few blocks, is relieved by leaning forward over a shopping cart, and occurs with normal pedal pulses. Which diagnosis best fits?

  1. Lumbar spinal stenosis with neurogenic claudication Correct answer.
  2. Lumbar radiculopathy from a disc herniation
  3. Hip osteoarthritis
  4. Vascular claudication from peripheral arterial disease

Explanation

Neurogenic claudication from lumbar canal stenosis worsens with lumbar extension during upright walking and improves with forward flexion, sitting, or leaning on a cart because flexion increases canal dimensions. Preserved pulses, bilateral and dermatomally vague leg symptoms, and relief with posture change distinguish it from vascular claudication.

Question 32Pain Assessment, Diagnosis, and Clinical Evaluation

A patient has chronic anterior abdominal pain. When supine, pain is unchanged or worse while the abdominal wall muscles are tensed by lifting the head, compared with relaxation. This response indicates which source of pain?

  1. Visceral abdominal pain
  2. Referred pain from the thoracic spine
  3. Somatic abdominal wall pain Correct answer.
  4. Peritoneal irritation

Explanation

This is a positive Carnett sign: if tensing the abdominal wall reproduces or worsens the pain, the tender structure lies in the wall itself, whereas a visceral source becomes less tender because the contracting muscle shields the viscera. It is a simple bedside maneuver for distinguishing abdominal wall pain from visceral disease.

Question 33Pain Assessment, Diagnosis, and Clinical Evaluation

A patient with diabetes reports burning feet and distal pinprick loss, but strength, reflexes, and nerve conduction studies are normal. Which test is most likely to confirm the suspected diagnosis?

  1. Skin punch biopsy with intraepidermal nerve fiber density Correct answer.
  2. Repeat nerve conduction studies after 6 months
  3. MRI of the lumbosacral plexus
  4. Needle electromyography of intrinsic foot muscles

Explanation

Small-fiber neuropathy affects thinly myelinated A-delta and unmyelinated C fibers, which large-fiber nerve conduction studies and electromyography cannot assess. Reduced intraepidermal nerve fiber density on a 3-mm punch biopsy, or abnormal thermal thresholds on quantitative sensory testing, supports the diagnosis when routine electrodiagnostics are normal.

Question 34Pain Assessment, Diagnosis, and Clinical Evaluation

A patient on high-dose morphine for chronic pain has escalating, diffuse pain and widespread tenderness as the dose rises, with no new structural pathology, and pain improves after the dose is reduced. Which phenomenon is this?

  1. Opioid-induced hyperalgesia Correct answer.
  2. Opioid tolerance
  3. Opioid withdrawal
  4. Pseudoaddiction

Explanation

Opioid-induced hyperalgesia is a paradoxical sensitization in which opioid exposure increases pain sensitivity, producing more diffuse pain and tenderness that worsen with dose escalation and improve with dose reduction or rotation. Tolerance is loss of analgesic effect at a given dose without heightened nociceptive sensitivity, and withdrawal requires abstinence or dose reduction with autonomic signs.

Question 35Pharmacologic Management of Pain

Which mechanism best explains the analgesic effect of acetaminophen?

  1. Agonism at mu-opioid receptors
  2. Inhibition of central prostaglandin synthesis Correct answer.
  3. Irreversible inhibition of platelet cyclooxygenase-1 in the periphery
  4. Blockade of voltage-gated sodium channels

Explanation

Acetaminophen reduces pain mainly through central inhibition of prostaglandin synthesis and modulation of descending serotonergic pathways. It has little peripheral anti-inflammatory activity and no clinically meaningful antiplatelet effect. This profile distinguishes it from NSAIDs, local anesthetics, and opioids.

Question 36Pharmacologic Management of Pain

According to US prescribing information, what is the maximum daily acetaminophen dose for a healthy adult without hepatic impairment?

  1. 2 g
  2. 8 g
  3. 3 g
  4. 4 g Correct answer.

Explanation

US labeling caps acetaminophen at 4,000 mg per day for adults without hepatic impairment or regular alcohol use. Many clinicians use a more conservative 3,000 mg per day ceiling for chronic dosing. Doses above the labeled maximum increase the risk of hepatotoxicity.

Question 37Pharmacologic Management of Pain

Which medication is the first-line antidote for opioid-induced respiratory depression?

  1. Flumazenil
  2. Buprenorphine
  3. Naloxone Correct answer.
  4. Naltrexone

Explanation

Naloxone is a short-acting competitive mu-opioid antagonist that rapidly reverses opioid-induced respiratory depression and sedation. It is given parenterally and titrated to restore adequate ventilation while limiting abrupt withdrawal. Naltrexone is a long-acting oral antagonist used for maintenance therapy rather than acute resuscitation.

Question 38Pharmacologic Management of Pain

NSAIDs produce analgesia and anti-inflammatory effects primarily by inhibiting which enzyme?

  1. Phosphodiesterase-4
  2. 5-lipoxygenase
  3. Angiotensin-converting enzyme
  4. Cyclooxygenase Correct answer.

Explanation

NSAIDs inhibit cyclooxygenase-1 and cyclooxygenase-2, reducing conversion of arachidonic acid into prostaglandins that sensitize nociceptors and drive inflammation. This same mechanism accounts for the class's gastrointestinal, renal, and cardiovascular adverse effects.

Question 39Pharmacologic Management of Pain

Tramadol relieves pain through which combination of mechanisms?

  1. Selective NMDA receptor blockade without opioid activity
  2. Selective cyclooxygenase-2 inhibition
  3. Mu-opioid agonism with monoamine reuptake inhibition Correct answer.
  4. Pure mu-opioid receptor antagonism

Explanation

Tramadol is a weak mu-opioid agonist whose analgesic effect also depends on inhibition of serotonin and norepinephrine reuptake. The monoaminergic action contributes to efficacy in neuropathic pain but also to seizure risk and serotonin syndrome when combined with serotonergic drugs.

Question 40Pharmacologic Management of Pain

Which medication is considered first-line pharmacotherapy for painful diabetic peripheral neuropathy?

  1. Ibuprofen
  2. Sumatriptan
  3. Oral morphine
  4. Duloxetine Correct answer.

Explanation

Guidelines recommend duloxetine, pregabalin, gabapentin, and tricyclic antidepressants as first-line agents for painful diabetic peripheral neuropathy. Opioids are reserved for refractory cases because of tolerance, misuse, and safety concerns. NSAIDs and triptans lack evidence for neuropathic pain.

Question 41Pharmacologic Management of Pain

Which agent is the specific antidote for acetaminophen overdose?

  1. Flumazenil
  2. Glucagon
  3. Naloxone
  4. N-acetylcysteine Correct answer.

Explanation

N-acetylcysteine replenishes hepatic glutathione stores and detoxifies the reactive metabolite NAPQI, preventing hepatic necrosis. It is most effective when administered within eight hours of ingestion, though later treatment still has benefit in established injury.

Question 42Pharmacologic Management of Pain

Topical capsaicin produces analgesia by acting at which target?

  1. Mu-opioid receptor agonism
  2. Voltage-gated sodium channel blockade
  3. GABA-A receptor potentiation
  4. TRPV1 channel agonism Correct answer.

Explanation

Capsaicin is a TRPV1 agonist that first activates and then defunctionalizes cutaneous nociceptors, depleting substance P and reducing pain signaling. The initial activation explains the burning sensation at application, which typically diminishes with repeated use.

Question 43Pharmacologic Management of Pain

A patient with a creatinine clearance of 25 mL/min is to start gabapentin for neuropathic pain. What is the most appropriate dosing approach?

  1. No adjustment is required
  2. Gabapentin is absolutely contraindicated
  3. The total daily dose should be reduced Correct answer.
  4. The dose should be increased to overcome reduced absorption

Explanation

Gabapentin is eliminated unchanged by the kidney, so its clearance falls in parallel with creatinine clearance. The daily dose or dosing interval must be adjusted to avoid accumulation and adverse effects such as sedation, ataxia, and myoclonus.

Question 44Pharmacologic Management of Pain

Which condition is a labeled contraindication to duloxetine?

  1. Stage 3 chronic kidney disease
  2. Uncontrolled narrow-angle glaucoma Correct answer.
  3. Long-standing type 2 diabetes mellitus
  4. Knee osteoarthritis

Explanation

Duloxetine is contraindicated in uncontrolled narrow-angle glaucoma because its noradrenergic activity can cause mydriasis and precipitate angle closure. It is also contraindicated with monoamine oxidase inhibitors and should be avoided in substantial alcohol use or chronic liver disease.

Question 45Pharmacologic Management of Pain

Which finding is the strongest reason to avoid a tricyclic antidepressant for neuropathic pain?

  1. Recent myocardial infarction Correct answer.
  2. Mild intermittent asthma
  3. Migraine with aura
  4. Hypothyroidism treated with levothyroxine

Explanation

Tricyclic antidepressants slow cardiac conduction and can provoke arrhythmias, so they are avoided after recent myocardial infarction and in significant conduction disease or uncompensated heart failure. Their anticholinergic and alpha-adrenergic effects also limit use in older adults.

Question 46Pharmacologic Management of Pain

How does methylnaltrexone relieve opioid-induced constipation while preserving analgesia?

  1. It is a peripherally restricted opioid antagonist Correct answer.
  2. It is a nonspecific opioid antagonist that crosses the blood-brain barrier
  3. It is a stimulant laxative with no receptor activity
  4. It is a centrally acting mu-opioid agonist

Explanation

Methylnaltrexone is a quaternary derivative of naltrexone with limited central nervous system penetration, so it blocks mu receptors in the gut without reversing analgesia. It is used for opioid-induced constipation that has not responded to conventional laxatives.

Question 47Pharmacologic Management of Pain

For which indication is the 5% lidocaine patch FDA-approved?

  1. Chronic nonspecific low back pain
  2. Fibromyalgia
  3. Painful diabetic polyneuropathy
  4. Postherpetic neuralgia Correct answer.

Explanation

The lidocaine 5% patch is approved for postherpetic neuralgia and works by blocking sodium channels in hyperexcitable cutaneous nociceptors. Systemic absorption is minimal, so systemic toxicity is rare. Its use in other neuropathic and musculoskeletal conditions is off-label.

Question 48Pharmacologic Management of Pain

Ketamine reduces pain and produces dissociative anesthesia mainly through which action?

  1. Positive allosteric modulation of GABA-A receptors
  2. Selective serotonin reuptake inhibition
  3. Mu-opioid receptor agonism
  4. Noncompetitive NMDA receptor antagonism Correct answer.

Explanation

Ketamine blocks the phencyclidine binding site of the NMDA receptor, reducing central sensitization and wind-up. At subanesthetic doses it is used as an adjunct for refractory pain and as an opioid-sparing agent.

Question 49Pharmacologic Management of Pain

Why does buprenorphine carry a lower risk of fatal respiratory depression than full mu-opioid agonists?

  1. Full mu-opioid agonism with rapid elimination from the brain
  2. Selective agonism at kappa-opioid receptors
  3. Pure mu-opioid receptor antagonism
  4. Partial mu-opioid agonism with high receptor affinity Correct answer.

Explanation

Buprenorphine produces submaximal activation of the mu receptor, so respiratory depression plateaus as the dose rises. Its very high receptor affinity also means it can displace full agonists and precipitate withdrawal in dependent patients.

Question 50Pharmacologic Management of Pain

Which combination places a patient at highest risk of serotonin syndrome?

  1. Metformin and insulin
  2. Tramadol and sertraline Correct answer.
  3. Gabapentin and pregabalin
  4. Acetaminophen and ibuprofen

Explanation

Tramadol inhibits serotonin reuptake, and combining it with a selective serotonin reuptake inhibitor can produce excessive serotonergic activity. Features include clonus, hyperreflexia, agitation, hyperthermia, and autonomic instability.