About this test
Sig codes are the shorthand prescribers use to communicate directions, and translating them accurately is a daily technician task the PTCE tests directly: the 2026 outline names sig codes, abbreviations, medical terminology and symbols in Domain 4.
This quiz drills the standard set (frequencies like BID/TID/QID, routes like PO/SL/PR, timing like AC/PC/HS) and (just as important for the Patient Safety domain) the ISMP error-prone abbreviations like U, IU, QD and trailing zeros that must be written out instead because they cause dangerous misreads.
New to the material? Work through our 2026 PTCB study guide first, then reinforce it with the full pharmacy abbreviations reference and Pharmacy Abbreviations Flashcards.
What's in the question bank
| Topic | Questions in bank |
|---|---|
| Frequency | 6 |
| Error Prone | 5 |
| Route | 4 |
| Dosage Form | 4 |
| Timing | 3 |
| Dispensing | 2 |
| Units | 1 |
Sample questions with answers
These 8 questions come straight from the 25-question bank the timed test above draws from. Work each one before you open the answer: recalling it cold is what moves it into long-term memory.
1. A prescription for 'bisacodyl 10 mg supp PR' involves which dosage form?
- A.Suppository
- B.Suspension
- C.Supplement
- D.Syrup
Show answer and explanation
Correct answer: A. Suppository
Supp means suppository, a solid dosage form inserted into the rectum (PR) or vagina where it melts or dissolves. The paired route abbreviation PR confirms rectal administration, distinguishing supp from the oral liquid susp.
2. A hospital order states the patient is NPO after midnight. What does NPO mean?
- A.Take by mouth as needed
- B.Normal saline only
- C.Nothing by mouth
- D.No known allergies
Show answer and explanation
Correct answer: C. Nothing by mouth
NPO comes from the Latin nil per os, meaning nothing by mouth, and is common before surgery or certain lab tests. It is essentially the opposite of PO (by mouth), and NKA/NKDA are the separate abbreviations for allergy status.
3. The abbreviation QAM directs a dose to be taken when?
- A.Every night at bedtime
- B.Every morning
- C.Every other day
- D.Every afternoon
Show answer and explanation
Correct answer: B. Every morning
QAM means every morning (quaque die ante meridiem, every day before noon) and is typical for drugs like levothyroxine that are taken on waking. Its evening counterpart is QPM, while QHS specifies bedtime.
4. A sig containing QHS instructs the patient to take the medication when?
- A.Every night at bedtime
- B.Every hour
- C.Every morning
- D.Every other night
Show answer and explanation
Correct answer: A. Every night at bedtime
QHS is from quaque hora somni, meaning every night at bedtime, and is common for statins such as simvastatin or for sleep aids. ISMP cautions that a handwritten qhs has been misread as qhr (every hour), a potentially serious frequency error.
5. Potassium chloride is commonly dosed as '20 mEq PO daily.' What does mEq stand for?
- A.Milligram
- B.Microgram
- C.Milliliter
- D.Milliequivalent
Show answer and explanation
Correct answer: D. Milliequivalent
mEq is the abbreviation for milliequivalent, a unit that expresses the chemical combining activity of an electrolyte rather than its weight. Electrolyte products such as potassium chloride are dosed in mEq, while most other oral drugs are dosed in milligrams.
6. A prescriber writes DAW on a prescription for Synthroid. What must the pharmacy do?
- A.Dispense any therapeutically equivalent generic
- B.Delay dispensing until an allergy check is completed
- C.Dispense the brand-name product exactly as written, with no generic substitution
- D.Dispense a one-week supply and await confirmation
Show answer and explanation
Correct answer: C. Dispense the brand-name product exactly as written, with no generic substitution
DAW means dispense as written, a prescriber instruction that the exact product ordered, usually the brand, must be dispensed without substitution. On third-party claims this is coded DAW 1, and it is common for narrow therapeutic index drugs such as levothyroxine.
7. An order marked 'stat' must be handled in what timeframe?
- A.Within 24 hours
- B.Immediately
- C.At the next scheduled dosing time
- D.Whenever the patient requests it
Show answer and explanation
Correct answer: B. Immediately
Stat comes from the Latin statim, meaning immediately, and flags an order that must be processed and administered right away. It is the opposite of routine or PRN orders, which follow normal scheduling.
8. According to ISMP, why should 'U' never be used as an abbreviation for units on insulin orders?
- A.It is only valid for international units
- B.It can be confused with the abbreviation mEq
- C.It applies only to veterinary prescriptions
- D.It can be misread as a zero or a 4, causing a tenfold or greater overdose
Show answer and explanation
Correct answer: D. It can be misread as a zero or a 4, causing a tenfold or greater overdose
ISMP lists U on its error-prone abbreviations list because a handwritten U has been mistaken for a zero or the number 4, so an order for 4U insulin has been read as 40 units. The safe practice, also required by The Joint Commission's Do Not Use list, is to write out the word unit.
Ready for the full timed run? Scroll back up and start the Abbreviations Quiz, or browse every free PTCB quiz by exam domain.
Key concepts to know
Frequencies, routes, timing
Frequencies: QD-equivalents (daily), BID (twice), TID (three times), QID (four times). Routes: PO (mouth), SL (sublingual), PR (rectal), TOP (topical). Timing: AC (before meals), PC (after meals), HS (bedtime), PRN (as needed).
The 'do not use' list
ISMP's error-prone abbreviations exist because they've caused real harm: 'U' read as zero (10-fold insulin overdose), 'QD' read as 'QID', trailing zeros (5.0 mg read as 50 mg), and 'MS' ambiguous between morphine sulfate and magnesium sulfate. The exam tests both what they mean and why they're banned.
Abbreviations Quiz: FAQ
Are sig code questions on the PTCE?
Yes, sig codes, abbreviations, and medical terminology are explicitly listed in Domain 4 (Order Entry & Processing) of the 2026 content outline, and error-prone abbreviations appear in Domain 3 (Patient Safety).
What's the most commonly confused abbreviation?
QD (daily) versus QID (four times daily) is the classic: a 4-fold dosing error from one letter, which is why ISMP says to write 'daily' instead.
Official sources checked
This quiz's content and explanations are built from and cross-checked against primary sources. Verify current exam facts directly with PTCB.