Thirty-two questions in one sitting, drawn from the three topics that cost people the most marks. Pick an answer and the explanation opens — nothing is gated.
Sit it in one go and keep a note of what you miss, because the pattern of misses is more useful than the score. Every answer links to the guide it came from, so a wrong one turns into a topic to read rather than a fact to memorise.
1. A prescriber's DEA number is AJ5641233. Using the check-digit method, is it valid?
Answer: B. Add the 1st, 3rd and 5th digits: 5 + 4 + 2 = 11. Add the 2nd, 4th and 6th: 6 + 1 + 3 = 10, then double it: 20. Add the two results: 11 + 20 = 31. The last digit of that sum is 1, but the 7th digit of the DEA number is 3. They disagree, so the number is not valid. On the exam the arithmetic is never the hard part — losing track of which digits are which is. More: How to verify a DEA number
2. In the DEA number AJ5641233 issued to Dr. Thomas Jones, what does the second letter, J, tell you?
Answer: C. The first letter marks the registrant type — A, B, F and G are practitioner-type letters, M marks a mid-level practitioner. The second letter is the first initial of the registrant's last name, which is why J fits Jones. A mismatch between that letter and the prescriber's surname is a classic exam flag for a forged or borrowed number. More: How to verify a DEA number
3. How does an NPI differ structurally from a DEA number?
Answer: B. A DEA number is two letters followed by seven digits. An NPI is 10 digits with no letters at all, and its 10th digit is a check digit validated with the Luhn 'double-add-double' mod-10 method — the same one used on credit cards. They identify the same prescriber for different purposes, and the exam likes to swap one for the other. More: How to verify a DEA number
4. A Schedule III prescription is presented. What is the federal refill limit?
Answer: B. Schedule II carries zero refills. Schedules III and IV allow up to five refills within six months of the date written — both halves matter, and running out of either one ends the prescription. Schedule V has no federal refill limit, though state law may impose one. The commonest error is carrying the CIII/CIV rule across the schedule line in either direction. More: DEA schedules, refills and transfers
5. A prescriber phones in an emergency oral Schedule II prescription. What must follow?
Answer: B. An emergency oral CII is limited to the quantity needed for the emergency period — commonly taught as about 72 hours — and the pharmacist must receive the signed written prescription, or a compliant electronic one, within 7 days. Miss the paperwork and the transaction was never completed. Form 222 is for ordering stock, not for dispensing, which is the trap in the fourth option. More: What makes a controlled substance prescription valid
6. A patient asks for a partial fill of a Schedule II prescription. Within what period must the remainder be supplied?
Answer: C. A CII may be partially filled at the request of the patient or the prescriber, with the remainder supplied within 30 days. Do not confuse this with the 7-day rule for the written follow-up to an emergency oral CII, or with the 72-hour emergency supply itself — the exam puts all three numbers in the same question set on purpose. More: DEA schedules, refills and transfers
7. How many line items may the current DEA Form 222 carry?
Answer: B. The legacy triplicate Form 222 was retired in October 2021 and allowed 10 line items. The current single-sheet Form 222 allows up to 20, and the same ordering can be done electronically through CSOS. If a question offers 'triplicate' as an option at all, that is the outdated answer. More: Ordering, receiving, storing and destroying controlled substances
8. Under the Combat Methamphetamine Epidemic Act, what are the federal pseudoephedrine purchase limits?
Answer: A. CMEA limits a purchaser to 3.6 grams per day, and 9 grams in a 30-day window at retail. The daily limit is the same for retail and mail order. Keep the two numbers the right way round: the smaller one is the daily cap. More: REMS, iPLEDGE and restricted drug programs
9. USP General Chapter <795> covers which of the following?
Answer: C. <800> is hazardous drugs, <797> is sterile compounding and <795> is nonsterile compounding. The PTCE tests these by number, so the chapter numbers have to be automatic. Worth knowing: nonsterile compounding was removed from the PTCE's own content outline in January 2026, but the chapter numbers still come up as identification. More: Hazardous drugs and USP <800>
10. Which containment primary engineering control is acceptable for hazardous sterile compounding?
Answer: C. Hazardous sterile work needs a Class II BSC — most commonly Type A2, with Type B2 used for volatile hazardous drugs — or a CACI, externally vented. A horizontal laminar-airflow workbench blows air at the operator and offers no personnel containment at all. A Type A1 is a real containment device but is not acceptable here: its minimum inflow is 75 ft/min against the 100 ft/min a Type A2 provides. More: Hazardous drugs and USP <800>
11. A product is recalled for a labeling deficiency that is unlikely to cause any adverse health consequence. Which recall class is it?
Answer: C. Class I means exposure could cause serious harm or death. Class II means temporary or medically reversible harm. Class III is primarily a compliance violation with minimal patient risk — a labeling or manufacturing deficiency. The hook that sticks: Class I could kill, Class II could hurt, Class III won't hurt. More: Drug recalls — Class I, II and III
12. Who initiates most drug recalls in the United States?
Answer: B. Most recalls are voluntary and begin with the manufacturer or distributor. For most human drugs the FDA cannot order a mandatory recall at all — it has that authority for devices, food, biologics and, under the 2018 SUPPORT Act, controlled substances. 'The FDA orders a recall' is a confident-sounding wrong answer. More: Drug recalls — Class I, II and III
13. Since 27 November 2023, which transaction records does DSCSA require at each handoff?
Answer: B. Transaction History sunset on 27 November 2023, which retired the old 'T3' framing. Two electronic records remain: Transaction Information, identifying product, lot, quantity, dates and trading partners, and the Transaction Statement, the seller's certification that the product was handled compliantly. Older study material still teaches T3 — that is how you spot material written before the change. More: DSCSA, 503A vs 503B and the drug supply chain
14. One pharmacy borrows stock from another to cover an urgent patient need. Which tracing document does a PTCE-style question expect?
Answer: B. For a pharmacy-to-pharmacy stock replenishment transfer, the expected answer is the transaction statement. Form 222 covers ordering Schedule I and II stock from a supplier and has nothing to do with DSCSA tracing, which is what makes it the attractive wrong answer here. More: DSCSA, 503A vs 503B and the drug supply chain
15. Why does ISMP flag q.d. as error-prone?
Answer: A. q.d. is read as q.i.d. far too often, which turns once-daily dosing into four times a day. Write 'daily' or 'every day'. q.o.d. is separately flagged because it reads as q.d. or q.i.d.; the bedtime/half-strength ambiguity belongs to HS. More: Sig codes, abbreviations and medical terminology
16. A prescription reads 'instil 1 gtt OS bid'. Where does the drop go?
Answer: B. OS is oculus sinister, the left eye. OD is the right eye, OU is both. The ear set runs AD, AS and AU. The pairs that catch people are OS/AS and OD/AD — one letter apart and a different organ. More: Sig codes, abbreviations and medical terminology
17. Which abbreviation should replace 'cc' on a prescription, and why?
Answer: A. ISMP lists cc as error-prone because handwritten cc is mistaken for U, which is itself on the list for being read as 0 or 4. Write mL. The two errors compound: a dose written in cc and misread as units can be off by orders of magnitude. More: Sig codes, abbreviations and medical terminology
18. Why are both SC and SQ flagged as error-prone, and what should be written instead?
Answer: A. SC and SQ are both mistaken for SL, which is sublingual — a completely different route. The safer forms are subcut or subcutaneous written out. This is one of the places where the abbreviation you will actually see in practice is the one you are marked wrong for writing. More: Sig codes, abbreviations and medical terminology
19. A prescription is written '5.0 mg'. What is the risk, and what is the correct form?
Answer: A. A trailing zero is misread as a ten-fold overdose when the decimal point is faint or lost — 5.0 mg becomes 50 mg. The mirror-image rule is the leading zero: never write .5 mg, always 0.5 mg, because a missing leading zero reads as 5 mg. One rule removes a zero, the other adds one, and the exam likes putting them in the same question. More: Sig codes, abbreviations and medical terminology
20. Why is HS on the do-not-use list?
Answer: B. HS is ambiguous: it can mean at bedtime or half strength. Write whichever you mean in full. It sits alongside D/C, which is ambiguous between discharge and discontinue — both are abbreviations whose two meanings lead to opposite actions. More: Sig codes, abbreviations and medical terminology
21. MS and MSO4 are flagged because they are ambiguous between which two drugs?
Answer: A. MS and MSO4 can each mean morphine sulfate or magnesium sulfate, and MgSO4 is separately confused with MSO4. Spell both out. These are drugs with entirely different indications and risks, which is why the ambiguity is on the list rather than merely untidy. More: Sig codes, abbreviations and medical terminology
22. 'Take 1 capsule TID for 10 days.' How many capsules are dispensed?
Answer: C. TID is three times daily. 1 capsule × 3 doses × 10 days = 30 capsules. The trap is QID, which is four times daily and would give 40 — and q.d. misread as q.i.d. is exactly how that error happens in practice. More: Sig codes, abbreviations and medical terminology
23. One tablespoon equals how many millilitres?
Answer: C. 1 tbsp = 15 mL = 3 tsp, and 1 tsp = 5 mL. The next one up is the fluid ounce at 30 mL (29.6 mL exactly), which is two tablespoons. These three conversions carry most of the household-measure questions on the exam. More: Sig codes, abbreviations and medical terminology
24. What does 'qs' or 'QSAD' direct you to do?
Answer: B. qs is quantum satis — a sufficient quantity — and QSAD is 'add a sufficient quantity to make'. It appears in compounding directions, where the final volume is specified rather than the amount of vehicle added. 'As directed' is UD, which is a different instruction entirely. More: Sig codes, abbreviations and medical terminology
25. Amoxicillin 500 mg PO TID × 7 days. Stock is 250 mg capsules. How many capsules?
Answer: B. Work in doses, not milligrams. Each 500 mg dose is 2 × 250 mg capsules. Three doses a day is 6 capsules a day. Over 7 days that is 42. The commonest error is dividing the total milligrams by the capsule strength and forgetting the frequency. More: Days supply — the method and the forms that catch people
26. Clindamycin 300 mg PO q6h, stock 150 mg capsules. How many capsules in a 24-hour supply?
Answer: C. q6h is four doses in 24 hours. Each 300 mg dose is 2 × 150 mg capsules. 2 × 4 = 8 capsules. Read q6h as 'four times a day' rather than counting hours forward from now — that is what keeps hospital 24-hour supply questions quick. More: Days supply — the method and the forms that catch people
27. Unless told otherwise, how many drops are assumed per millilitre?
Answer: C. The convention is 1 mL = 20 drops, and the exam relies on it for ophthalmic days-supply questions. A 5 mL bottle therefore holds about 100 drops. If a question states a different drop factor, use the stated one — an infusion set's gtt/mL is a separate number entirely. More: Days supply — the method and the forms that catch people
28. Tobramycin ophthalmic, 2 drops in each eye six times daily × 7 days, 5 mL bottles. How many bottles?
Answer: B. 4 drops per dose (both eyes) × 6 doses = 24 drops a day; × 7 days = 168 drops. At 20 drops per mL that is 8.4 mL, which is 1.68 bottles. Round UP to 2. Ophthalmic dispensing always rounds up, because loss during administration is expected — rounding down leaves the patient short mid-course. More: Days supply — the method and the forms that catch people
29. Round 7.84621 to the nearest hundredth.
Answer: B. The hundredths place is the second decimal, 4. Look one place to its right: 6, which is 5 or greater, so round up to 7.85. Tenths would give 7.8 and thousandths 7.846 — the exam offers all three, so read which place is asked for before doing anything. More: Days supply — the method and the forms that catch people
30. A calculation gives 3.847 mL, to be measured in a 5 mL oral syringe marked every 0.5 mL. What should you do?
Answer: B. Practical rounding: the answer has to be measurable with the device in hand. A syringe marked in 0.5 mL increments cannot deliver 3.847 mL, so the arithmetic being right does not make the answer usable. The same rule stops you reporting 7.3 days when the prescription is written in whole days. More: Days supply — the method and the forms that catch people
31. Diphenhydramine is dosed 5 mg/kg/day. A child weighs 35 lb. What is the daily dose?
Answer: A. Convert first: 35 lb ÷ 2.2 = 15.9 kg. Then 5 mg × 15.9 = 79.5 mg/day. Set it up so the units cancel — mg = (5 mg/kg/day) × (1 kg / 2.2 lb) × 35 lb × 1 day — and the pounds disappear, leaving mg. The 175 mg option is what you get by forgetting to convert at all. More: Days supply — the method and the forms that catch people
32. What is the first step of dimensional analysis?
Answer: B. Write the target unit first, then arrange every given value and conversion factor so that all other units cancel, and do the arithmetic last. Setting the target first is what makes the cancellation a check on your setup: if the units do not cancel to what was asked for, the setup is wrong and no amount of correct arithmetic will save it. More: Days supply — the method and the forms that catch people
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