Controlled Substances
Help Questions
NAPLEX › Controlled Substances
A 43-year-old female presents to pick up new prescriptions from an urgent care visit for acute dental pain after extraction. She is currently taking clonazepam (Schedule IV) 1 mg by mouth twice daily, sertraline 100 mg by mouth daily, and zolpidem (Schedule IV) 10 mg by mouth at bedtime as needed (uses most nights). Allergies: hydrocodone (itching). Medical history: generalized anxiety disorder, insomnia. Labs: serum creatinine 0.8 mg/dL (0.6–1.3), AST 22 U/L (10–40), ALT 19 U/L (7–56). New prescription: tramadol (Schedule IV) 50 mg by mouth every 6 hours as needed for pain, #20. What is the best recommendation for this patient's therapy?
Dispense tramadol as written and instruct the patient to double zolpidem on nights with more pain to improve sleep
Dispense tramadol as written and recommend urine drug screening every 24 hours while taking tramadol
Recommend non-opioid analgesics first and contact the prescriber to avoid tramadol due to additive central nervous system depression with clonazepam and zolpidem
Switch tramadol to meperidine 50 mg by mouth every 4 hours as needed because it has less interaction with benzodiazepines
Explanation
This question evaluates the recognition of dangerous drug interactions with controlled substances in the setting of acute pain management. The critical patient-specific factor is the concurrent use of two CNS depressants (clonazepam and zolpidem) with a proposed third CNS depressant (tramadol), creating significant risk for respiratory depression and sedation. Option A is correct because it prioritizes non-opioid alternatives and recognizes the serious interaction potential between tramadol and the existing benzodiazepine/Z-drug combination. Option B is dangerously incorrect as it not only ignores the interaction but suggests doubling the zolpidem dose, which could be fatal. Option C is wrong because meperidine has even more concerning interactions and toxicity risks, especially with serotonergic medications like sertraline. Option D inappropriately suggests excessive monitoring without addressing the core safety issue. The clinical framework is that combining multiple CNS depressants significantly increases overdose risk, and alternative pain management strategies should be explored first, especially for acute dental pain which typically responds well to NSAIDs and acetaminophen.
A 33-year-old female (weight 59 kg) is taking lorazepam (Schedule IV) 1 mg at bedtime for 6 months for insomnia and wants to stop because she is pregnant (8 weeks). Current medications: lorazepam as above and prenatal vitamin. Allergies: none. Medical history: insomnia, generalized anxiety disorder; no substance use disorder. Labs: not available. Which controlled substance management action is most appropriate for this patient?
Stop lorazepam abruptly today to avoid fetal exposure, without tapering
Increase lorazepam to 2 mg nightly to reduce pregnancy-related anxiety and improve sleep
Recommend a gradual taper to reduce withdrawal risk and coordinate with prescriber/OB provider; emphasize nonpharmacologic sleep strategies during pregnancy
Switch to diazepam 10 mg nightly immediately because it is safer in pregnancy than lorazepam
Explanation
This question evaluates the management of benzodiazepine discontinuation in pregnancy, focusing on withdrawal risks and fetal safety for Schedule IV controlled substances like lorazepam. The key patient-specific factor is the patient's 6-month use of lorazepam for insomnia, now complicated by early pregnancy, where abrupt cessation could cause maternal withdrawal symptoms harmful to both mother and fetus. Recommending a gradual taper in coordination with the prescriber and OB provider is the best choice as it minimizes withdrawal risks while incorporating nonpharmacologic strategies to support sleep during pregnancy. Abruptly stopping lorazepam is suboptimal due to high withdrawal risk, increasing the dose could heighten fetal exposure and dependence, and switching to diazepam is not safer given its longer half-life and potential for accumulation in pregnancy. A common misconception in controlled substance management is that all benzodiazepines are interchangeable or that pregnancy necessitates immediate cessation without tapering, ignoring withdrawal dangers. A transferable pearl is to use validated tools like the Clinical Institute Withdrawal Assessment for Benzodiazepines when tapering. Guidelines emphasize shared decision-making, risk-benefit assessment, and monitoring for misuse in pregnant patients on controlled substances.
A 56-year-old female (weight 76 kg) is on long-term zolpidem (Schedule IV) 10 mg nightly for insomnia and reports needing 2 tablets nightly to sleep. Current medications: zolpidem 10 mg nightly, venlafaxine XR 150 mg daily, and melatonin 5 mg nightly. Allergies: none. Medical history: insomnia, major depressive disorder; no substance use disorder history. Labs: serum creatinine 0.9 mg/dL (0.6–1.3). Which controlled substance management action is most appropriate for this patient?
Recommend increasing zolpidem to 20 mg nightly indefinitely because tolerance is expected
Recommend a gradual taper/discontinuation plan and nonpharmacologic insomnia strategies; contact prescriber to reassess therapy rather than escalating zolpidem dose
Advise taking zolpidem with 2 glasses of wine to enhance hypnotic effect
Add alprazolam (Schedule IV) 1 mg nightly to improve sleep while continuing zolpidem
Explanation
This question assesses the management of tolerance and dependence in long-term non-benzodiazepine hypnotic use for insomnia. The key patient-specific factor is the patient's self-escalation to double zolpidem doses, indicating potential dependence alongside venlafaxine, which may worsen insomnia if not addressed. Option A is the best choice as recommending a gradual taper with nonpharmacologic strategies and prescriber reassessment prevents withdrawal while avoiding escalation. Option B is incorrect because indefinite increases risk adverse effects, a misconception that tolerance justifies higher doses. Option C is suboptimal as adding alprazolam compounds sedation; option D dangerously enhances effects with alcohol. A pearl is that zolpidem is recommended for short-term use per AASM guidelines. Use a deprescribing framework incorporating cognitive behavioral therapy for insomnia in controlled substance management.
A 48-year-old male (weight 90 kg) on chronic pain therapy presents a handwritten prescription for hydromorphone (Schedule II) 4 mg tablets: “Take 1 tablet every 4–6 hours prn pain, dispense 180.” The prescription is missing the prescriber DEA number and has no patient address; the patient is paying cash and refuses to provide ID. Current medications per patient: hydromorphone, carisoprodol (not controlled federally), and zolpidem (Schedule IV) 10 mg at bedtime. Allergies: none. Medical history: chronic back pain; history of heroin use disorder (in remission). Which action should the pharmacist take regarding this prescription?
Change the quantity to 30 tablets and dispense without contacting the prescriber to reduce risk
Fill the prescription because Schedule II medications do not require prescriber DEA number on the prescription
Hold dispensing and contact the prescriber to verify and obtain missing required information; document due diligence and check PDMP before deciding to dispense
Refuse to fill and immediately destroy the prescription without documenting because it is incomplete
Explanation
This question assesses the verification process for incomplete or suspicious Schedule II prescriptions to prevent diversion. The key patient-specific factors include the missing DEA number and patient address, cash payment, refusal of ID, and history of heroin use disorder, raising red flags for legitimacy. Option C is the best choice as holding, contacting the prescriber for missing information, documenting, and checking PDMP ensures compliance with DEA requirements before dispensing. Option A is incorrect because Schedule II prescriptions must include DEA numbers, a regulatory misconception. Option B is suboptimal as destroying without documentation violates protocols; option D involves unauthorized changes, risking legal issues. A clinical pearl is that pharmacists have 'corresponding responsibility' to resolve red flags per 21 CFR 1306.04. Implement a decision framework using PDMP and prescriber verification for all suspicious controlled substance prescriptions.
A 63-year-old female (weight 58 kg) is taking methadone (Schedule II) 10 mg orally three times daily for chronic pain prescribed by her primary care provider. She is newly prescribed clarithromycin 500 mg twice daily for 10 days by an urgent care clinic. Current medications: methadone as above, sertraline 100 mg daily, and furosemide 20 mg daily. Allergies: none. Medical history: chronic pain, heart failure. Labs: potassium 3.2 mEq/L (3.5–5.0), magnesium 1.6 mg/dL (1.7–2.2), serum creatinine 1.1 mg/dL (0.6–1.3). Which controlled substance management action is most appropriate for this patient?
Dispense clarithromycin and methadone without intervention because antibiotics do not interact with opioids
Monitor QT interval once yearly only, regardless of interacting medications or electrolyte abnormalities
Contact prescribers to avoid or change clarithromycin due to increased methadone levels and QT prolongation risk; recommend correcting electrolytes and consider electrocardiogram monitoring
Increase methadone dose during clarithromycin therapy to prevent withdrawal
Explanation
This question tests the management of drug interactions between methadone and macrolides in patients with cardiac risk factors. The key patient-specific factors are clarithromycin's potential to increase methadone levels and prolong QT interval, exacerbated by hypokalemia, hypomagnesemia, and heart failure. Option B is the best choice as contacting prescribers to avoid clarithromycin, correct electrolytes, and consider ECG monitoring prevents torsades de pointes and overdose. Option A is incorrect because antibiotics like clarithromycin do interact via CYP3A4 inhibition, a common oversight. Option C is suboptimal as increasing methadone risks toxicity; option D underestimates acute risks with insufficient monitoring. A pearl is that methadone requires QT monitoring per FDA black box warnings when combined with QT-prolonging drugs. Use a framework assessing electrolyte status and ECG needs for high-risk opioid interactions.
A 19-year-old male (weight 72 kg) brings a prescription for amphetamine/dextroamphetamine immediate-release (Schedule II) 30 mg tablets: take 1 tablet twice daily. The patient previously filled amphetamine/dextroamphetamine 20 mg twice daily 7 days ago at another pharmacy (per PDMP) and states the new dose is due to “not working.” Current medications: amphetamine/dextroamphetamine as above, none else. Allergies: none. Medical history: ADHD; no substance use disorder history documented. Labs: not available. Which action should the pharmacist take regarding this prescription?
Fill both prescriptions and counsel to alternate doses every other day
Change the medication to lisdexamfetamine 70 mg daily without prescriber authorization
Decline to fill and contact the prescriber to verify the dose change and timing; document and assess for early refill/escalation concerns using PDMP data
Fill the new prescription immediately and instruct the patient to discard the previous supply
Explanation
This question evaluates the handling of potential dose escalation or early refills for stimulants in young adults. The key patient-specific factors are the recent fill of a lower dose and the quick escalation to 30 mg without clear rationale, per PDMP, raising concerns for misuse or diversion. Option B is the best choice as declining to fill immediately, contacting the prescriber for verification, and documenting with PDMP assessment prevents inappropriate escalation and ensures therapeutic legitimacy. Option A is incorrect because dispensing without verification risks enabling abuse, a misconception in rapid dose changes. Option C is suboptimal as filling both promotes overuse; option D involves unauthorized substitution. A clinical pearl is that stimulant doses should be titrated gradually per APA ADHD guidelines. Apply a decision framework reviewing PDMP for patterns before approving controlled substance dose changes.
A 38-year-old male (weight 84 kg) is receiving oxycodone immediate-release (Schedule II) 15 mg every 6 hours as needed for chronic pain. A urine drug test from last week (shared by prescriber) is negative for oxycodone and positive for benzodiazepines; the patient is not prescribed any benzodiazepine. Current medications: oxycodone as above, naproxen 500 mg twice daily. Allergies: none. Medical history: chronic pain after injury; history of stimulant use disorder (in remission). Labs: serum creatinine 1.0 mg/dL (0.6–1.3). Which controlled substance management action is most appropriate for this patient?
Increase oxycodone dose because a negative test proves the patient metabolizes oxycodone rapidly
Ignore the urine drug test results and continue dispensing opioids as long as the prescription is valid
Advise the patient to take extra oxycodone before the next urine test so it will be positive
Contact the prescriber to discuss the unexpected urine drug test findings and coordinate next steps (confirmatory testing, reassessment of therapy, and risk mitigation) before dispensing
Explanation
This question tests the response to unexpected urine drug test results in opioid therapy monitoring. The key patient-specific factors are the negative oxycodone and positive benzodiazepine results, unexplained in a patient with stimulant use disorder history, suggesting possible nonadherence or diversion. Option B is the best choice as contacting the prescriber for discussion, confirmatory testing, and therapy reassessment ensures accurate interpretation and safe continuation before dispensing. Option A is incorrect because ignoring results neglects risk mitigation, a misconception that valid prescriptions override monitoring. Option C is suboptimal as assuming rapid metabolism lacks evidence; option D promotes manipulation of tests. A clinical pearl is that UDTs should include confirmatory testing for unexpected results per CDC guidelines. Employ a framework interpreting UDTs with patient history and PDMP for controlled substance stewardship.
A 29-year-old female (weight 64 kg) presents with a written prescription for methylphenidate immediate-release (Schedule II) for attention-deficit/hyperactivity disorder. Current medications: methylphenidate immediate-release 10 mg by mouth twice daily (last filled 10 days ago for #60), escitalopram 10 mg by mouth daily. Allergies: none. Medical history: ADHD; history of stimulant misuse in college (self-reported, no current treatment). Labs: not available. The new prescription is for methylphenidate immediate-release 20 mg by mouth three times daily, #90, with no diagnosis written and the prescriber’s DEA number is missing. Which action should the pharmacist take regarding this prescription?
Dispense the prescription as written because Schedule II prescriptions do not require the prescriber’s DEA number if handwritten
Refuse to dispense and destroy the prescription because any missing element makes it invalid and non-correctable
Contact the prescriber to verify and obtain required information (including DEA number) and assess appropriateness before dispensing
Change the dose to 10 mg three times daily based on the prior fill and dispense without contacting the prescriber
Explanation
This question tests knowledge of Schedule II prescription requirements and appropriate pharmacist response to incomplete prescriptions. The critical issue is a Schedule II prescription missing the prescriber's DEA number, which is a federal requirement for all controlled substance prescriptions. Option C is correct because federal law requires specific elements on Schedule II prescriptions including the prescriber's DEA number, and while some elements can be added after verbal verification, the pharmacist must contact the prescriber to obtain missing information and verify the prescription's legitimacy. Option A is incorrect because all Schedule II prescriptions require a DEA number regardless of whether they are handwritten or electronic. Option B is wrong because missing information can often be corrected through prescriber contact rather than destroying the prescription. Option D represents illegal prescription modification and bypasses necessary verification steps. The regulatory framework requires that Schedule II prescriptions contain all required elements including patient name, drug name/strength, quantity, directions, prescriber signature, and DEA number; missing elements must be verified with the prescriber before dispensing.
A 67-year-old male (weight 76 kg) is brought to the pharmacy by his daughter after starting a new medication for anxiety. Current medications include alprazolam (Schedule IV) 1 mg by mouth three times daily (started 10 days ago), diphenhydramine 25 mg by mouth at bedtime as needed, lisinopril 20 mg by mouth daily, and metformin 1000 mg by mouth twice daily. Allergies: penicillin (rash). Medical history: type 2 diabetes, hypertension, mild cognitive impairment; no known substance use disorder. Labs: serum creatinine 1.2 mg/dL (0.6–1.3). The daughter reports he fell twice this week and is “confused and very sleepy.” What is the most important monitoring parameter for this medication?
Monitor absolute neutrophil count weekly for the first 6 months
Monitor for falls, confusion, and excessive sedation, especially during initiation and dose increases
Monitor serum potassium daily due to risk of hyperkalemia from alprazolam
Monitor international normalized ratio (INR) twice weekly due to increased bleeding risk
Explanation
This question addresses monitoring parameters for benzodiazepines in elderly patients with cognitive impairment. The key patient-specific factors are advanced age (67 years), mild cognitive impairment, and the recent initiation of a high-dose benzodiazepine regimen combined with another anticholinergic/sedating medication (diphenhydramine). Option A is correct because falls, confusion, and excessive sedation are the most critical safety concerns with benzodiazepines in elderly patients, particularly those with baseline cognitive impairment. Option B is incorrect as neutropenia is not a concern with alprazolam (this would be relevant for clozapine). Option C is wrong because alprazolam does not affect coagulation or INR. Option D is incorrect as alprazolam does not cause hyperkalemia. The clinical pearl is that benzodiazepines are potentially inappropriate medications in elderly patients (Beers Criteria) due to increased sensitivity and risk of falls, cognitive decline, and delirium, requiring close monitoring for these adverse effects rather than laboratory parameters.
A 58-year-old male (weight 92 kg) presents to the pharmacy for a refill of his chronic pain regimen for lumbar radiculopathy. Current medications include oxycodone extended-release (Schedule II) 20 mg by mouth every 12 hours, oxycodone immediate-release (Schedule II) 5 mg by mouth every 6 hours as needed (uses 3–4 tablets/day), gabapentin 600 mg by mouth three times daily, and duloxetine 60 mg by mouth daily. Allergies: none. Medical history: chronic low back pain, COPD, obstructive sleep apnea (not using CPAP), depression; history of alcohol use disorder in sustained remission (8 years). Labs: serum creatinine 1.0 mg/dL (0.6–1.3), AST 28 U/L (10–40), ALT 31 U/L (7–56). The patient reports increased daytime sleepiness and his spouse reports loud snoring and “pauses in breathing.” Which controlled substance management action is most appropriate for this patient?
Assess overdose risk, provide naloxone, counsel to avoid other sedatives/alcohol, and recommend urgent evaluation and treatment of sleep apnea before escalating opioids
Continue the current opioid regimen and schedule urine drug screening every 12 months because he is on a stable dose
Dispense the refills as written and counsel only on constipation and safe storage because sedation is expected with opioids
Initiate an opioid taper by decreasing the total daily oxycodone dose by 50% every 2 days until discontinued
Explanation
This question tests the management of opioid therapy in a patient with multiple risk factors for respiratory depression. The key patient-specific factor is untreated obstructive sleep apnea combined with COPD and chronic opioid use, creating a dangerous combination for opioid-induced respiratory depression. Option D is the best choice because it addresses the immediate safety concerns by assessing overdose risk, providing naloxone for emergency reversal, counseling on avoiding additional CNS depressants, and recommending urgent treatment of sleep apnea before any opioid escalation. Option A is incorrect because continuing the current regimen without addressing the respiratory risks could be fatal. Option B fails to recognize the serious safety concerns and focuses only on minor side effects. Option C suggests an inappropriately rapid taper that could precipitate withdrawal and doesn't address the underlying sleep apnea. The clinical pearl is that untreated sleep apnea is a major risk factor for opioid-related mortality, and patients should have sleep disorders adequately treated before initiating or escalating opioid therapy.