PTCB Quiz Prep

Sig Code Practice Questions with Answers

Updated ยท aligned to the 2026 PTCE outline

Translate the frequency, timing and route abbreviations that appear on almost every prescription you will process.

23 questionsAnswers includedUntimedEvery answer cited100% free

Key takeaways

  • BID is twice daily, TID three times, QID four times. QD and QOD are on the ISMP do-not-use list.
  • AC is before meals, PC after meals, HS at bedtime, PRN as needed.
  • PO is by mouth, SL sublingual, PR rectal, OD/OS/OU right/left/both eyes.
  • gtt means drop. Roman numerals still appear in quantities: i, ii, iii, iv, v.

A sig is the directions portion of a prescription, and it is written in a shorthand of Latin abbreviations. Reading it correctly is the difference between a patient taking a drug twice a day and four times a day, so the PTCE tests it heavily inside the Order Entry and Processing domain.

These questions are untimed and every answer is on the page. Cover the options, translate the sig out loud, then check yourself. Sig translation is pure recall, and recall improves faster when you retrieve the answer before you see it.

Want the same material as a timed, randomized run instead? Try the full pharmacy abbreviations reference, the timed Order Entry quiz, and the Order Entry & Processing domain guide.

All 23 sig codes questions and answers

Each answer is followed by an explanation and a link to the primary source it was checked against.

  1. 1. A new prescription reads: "Amoxicillin 500 mg, i cap PO BID x 10 days." Which set of patient directions correctly translates this sig?

    • A.Take one capsule by mouth once daily for 10 days
    • B.Take two capsules by mouth once daily for 10 days
    • C.Take one capsule by mouth twice daily for 10 days
    • D.Take one capsule by mouth every other day for 10 days

    Answer: C. Take one capsule by mouth twice daily for 10 days

    PO means by mouth and BID means twice daily, so the patient takes one capsule by mouth two times each day. The Roman numeral i indicates one capsule per dose, and the course length of 10 days comes directly from the sig.

    Source: pharmacytechscholar.com

  2. 2. The abbreviation AC in a prescription sig instructs the patient to take the dose at what time?

    • A.Before meals
    • B.After meals
    • C.At bedtime
    • D.In the morning

    Answer: A. Before meals

    AC comes from the Latin ante cibum and means before meals. It is commonly seen on medications such as sulfonylureas or rapid-acting insulins that work best when taken shortly before eating, while PC (post cibum) is the abbreviation for after meals.

    Source: pharmacytechnologysolutions.ca

  3. 3. A technician is entering a prescription for timolol 0.5% ophthalmic solution with the sig "1 gtt OS BID." How should the directions read on the label?

    • A.Instill 1 drop in the right eye twice daily
    • B.Instill 1 drop in the left eye twice daily
    • C.Instill 1 drop in each eye twice daily
    • D.Instill 1 drop in the left ear twice daily

    Answer: B. Instill 1 drop in the left eye twice daily

    OS designates the left eye, gtt means drop, and BID means twice daily. OD would indicate the right eye and OU each eye, while the ear abbreviations use A (AD, AS, AU), so confusing these letters would send the drug to the wrong site.

    Source: pharmacytechnologysolutions.ca

  4. 4. A prescription for nitroglycerin 0.4 mg tablets carries the sig "i tab SL PRN chest pain." What do these directions tell the patient to do?

    • A.Swallow one tablet whole every day to prevent chest pain
    • B.Chew one tablet with water at the first sign of chest pain
    • C.Insert one tablet rectally as needed for chest pain
    • D.Dissolve one tablet under the tongue as needed for chest pain

    Answer: D. Dissolve one tablet under the tongue as needed for chest pain

    SL means sublingual, or under the tongue, and PRN means as needed (when required). Nitroglycerin is placed under the tongue for rapid absorption during an angina episode rather than being swallowed on a schedule.

    Source: pharmacytechnologysolutions.ca

  5. 5. A sig ending in "HS" directs the patient to take the medication at what time?

    • A.With the first meal of the day
    • B.At bedtime
    • C.Every hour as needed
    • D.One hour before lunch

    Answer: B. At bedtime

    HS stands for hora somni, meaning at bedtime, and is common on sedating medications and some cholesterol-lowering drugs. Because handwritten HS can also be misread as half-strength, many safety organizations recommend spelling out the intended timing.

    Source: pharmacytechnologysolutions.ca

  6. 6. An otic prescription is written as "ii gtt AU BID." Which directions belong on the label?

    • A.Instill 2 drops into each ear twice daily
    • B.Instill 2 drops into the right ear twice daily
    • C.Instill 2 drops into each eye twice daily
    • D.Instill 11 drops into the left ear once daily

    Answer: A. Instill 2 drops into each ear twice daily

    The Roman numeral ii equals two, gtt means drops, and AU designates each (both) ears. AD would be the right ear only and AS the left ear, while the O abbreviations (OD, OS, OU) refer to the eyes, not the ears.

    Source: pharmacytechnologysolutions.ca

  7. 7. A prescriber writes "Sucralfate 1 g, i tab PO AC & HS." Assuming the patient eats three meals daily, how many tablets will the patient take in one full day?

    • A.Two tablets
    • B.Three tablets
    • C.Four tablets
    • D.Six tablets

    Answer: C. Four tablets

    AC means before meals, which accounts for three doses with three daily meals, and HS adds one more dose at bedtime. Three mealtime tablets plus one bedtime tablet equals four tablets per day, which is why this sig is often entered as QID scheduling in the pharmacy system.

    Source: pharmacytechnologysolutions.ca

  8. 8. Which sig abbreviation indicates that a medication should be taken four times a day?

    • A.QD
    • B.QOD
    • C.Q4H
    • D.QID

    Answer: D. QID

    QID (quater in die) means four times a day. QD means daily, QOD means every other day, and Q4H means every 4 hours, which would actually produce six doses across a full 24-hour period rather than four.

    Source: denalirx.com

  9. 9. A faxed prescription contains the handwritten frequency "QOD." According to the ISMP error-prone abbreviations list, why does this abbreviation create risk during order entry?

    • A.It can be misread as QD (daily) or QID (four times daily)
    • B.It can be misread as a Roman numeral quantity
    • C.It is only approved for use on veterinary prescriptions
    • D.It refers to two different routes of administration

    Answer: A. It can be misread as QD (daily) or QID (four times daily)

    ISMP lists q.o.d./QOD as error-prone because a poorly written 'o' can make it look like q.d. (daily) or q.i.d. (four times daily), causing a dangerous frequency error. The recommended practice is to write out 'every other day' instead of using the abbreviation.

    Source: ismp.org

  10. 10. A prescription for prednisone 10 mg reads "ss tab PO QAM." What dose should the patient take?

    • A.One tablet every morning
    • B.One-half tablet every morning
    • C.Two tablets every other morning
    • D.One-half tablet every evening

    Answer: B. One-half tablet every morning

    The apothecary abbreviation ss means one-half, so the patient takes half of a 10 mg tablet (5 mg) each dose. QAM indicates the dose is taken every morning, not in the evening (QPM) or on alternating days.

    Source: pharmacytechnologysolutions.ca

  11. 11. A sig reads: '1 tab PO BID.' How often should the patient take this medication?

    • A.Three times a day
    • B.Twice a day
    • C.Four times a day
    • D.Every other day

    Answer: B. Twice a day

    BID comes from the Latin bis in die, meaning twice a day, typically spaced about 12 hours apart. It is one of the most common frequency abbreviations, alongside TID (three times daily) and QID (four times daily).

    Source: medlineplus.gov

  12. 12. The abbreviation TID on a prescription instructs the patient to take the medication how often?

    • A.Twice a day
    • B.Four times a day
    • C.Every three hours
    • D.Three times a day

    Answer: D. Three times a day

    TID stands for the Latin ter in die, meaning three times a day, usually at roughly 8-hour intervals. It should not be confused with TIW (three times a week), which ISMP flags as error-prone.

    Source: medlineplus.gov

  13. 13. What does QID mean when it appears in prescription directions?

    • A.Four times a day
    • B.Every four hours
    • C.Once daily
    • D.Four times a week

    Answer: A. Four times a day

    QID is from the Latin quater in die and means four times a day, typically around every six hours while awake. It differs from q4h, which means every 4 hours around the clock, a distinction that changes the total daily doses.

    Source: medlineplus.gov

  14. 14. A medication order that includes PRN should be administered how?

    • A.As needed
    • B.As directed
    • C.Immediately
    • D.Every night

    Answer: A. As needed

    PRN is from the Latin pro re nata, meaning as needed, and is used for symptom-driven medications such as pain relievers or rescue inhalers. It differs from UD or ut dictum (as directed) and stat (immediately).

    Source: medlineplus.gov

  15. 15. 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

    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.

    Source: mn.gov

  16. 16. 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

    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.

    Source: mn.gov

  17. 17. The abbreviation AC in a sig such as 'take 1 tablet AC' means the dose should be taken when?

    • A.After meals
    • B.Before meals
    • C.Around the clock
    • D.At bedtime

    Answer: B. Before meals

    AC is from the Latin ante cibum, meaning before meals, and is common for drugs like sulfonylureas or sucralfate that work best on an empty stomach. Its counterpart PC (post cibum) means after meals.

    Source: mn.gov

  18. 18. What does PC indicate about the timing of a dose?

    • A.Take before meals
    • B.Take at bedtime
    • C.Take after meals
    • D.Take as needed

    Answer: C. Take after meals

    PC comes from the Latin post cibum and means after meals, often used for medications that can upset an empty stomach. It is the mirror of AC (before meals), and the two are classic look-alike timing codes.

    Source: mn.gov

  19. 19. In the sig 'i tab PO HS,' the abbreviation HS is interpreted as what?

    • A.Every hour
    • B.Half a tablet
    • C.Before breakfast
    • D.At bedtime

    Answer: D. At bedtime

    HS comes from the Latin hora somni and means at bedtime. Because lowercase hs (bedtime) and HS (half-strength) have been confused with each other, ISMP lists this pair as error-prone and recommends writing out the intended meaning.

    Source: mn.gov

  20. 20. A prescription marked PO tells the pharmacy the medication is to be taken by which route?

    • A.By rectum
    • B.Under the tongue
    • C.By mouth
    • D.In the right eye

    Answer: C. By mouth

    PO is from the Latin per os, meaning by mouth or orally, and is the most common route abbreviation. Rectal administration is PR and sublingual is SL, two similar route codes that must not be mixed up.

    Source: mn.gov

  21. 21. The route abbreviation PR directs that a medication be administered where?

    • A.Rectally
    • B.Orally
    • C.Vaginally
    • D.Topically on the skin

    Answer: A. Rectally

    PR means per rectum, the route used for products such as suppositories and some enemas. It contrasts with PO (by mouth) and PV (per vagina), so reading the route letters carefully matters.

    Source: mn.gov

  22. 22. Nitroglycerin tablets marked SL should be administered by which route?

    • A.Injected under the skin
    • B.Into the left eye
    • C.Applied to the skin
    • D.Under the tongue

    Answer: D. Under the tongue

    SL means sublingual, placed under the tongue to dissolve so the drug absorbs directly into the bloodstream. ISMP notes that a poorly written SC (subcutaneous) has been mistaken for SL, which is one reason SUBQ or full words are preferred for injections.

    Source: mn.gov

  23. 23. 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

    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.

    Source: drugs.com

Sig Codes: FAQ

What does a sig code mean on a prescription?

The sig is the prescriber's directions to the patient, written in abbreviations drawn from Latin. 'Sig: 1 tab PO BID' means take one tablet by mouth twice a day. Pharmacy technicians translate the sig into plain English for the prescription label during order entry.

How many sig codes do I need to know for the PTCB exam?

There is no official list, but the frequency, route, timing and dosage-form abbreviations are the ones that recur. Our full reference covers 159 abbreviations; the roughly 40 in these practice questions are the ones that show up most often in real order entry.

Which sig abbreviations are error-prone?

ISMP flags QD, QOD, U, IU, MS, MSO4 and MgSO4 among others, because they are misread often enough to cause harm. QD has been misread as QID, and U as a zero, turning 4U into 40 units. Expect the exam to test that you recognize these as abbreviations to avoid rather than use.

Are these sig code questions free?

Yes. Every question, answer and explanation on this page is free and needs no sign-up. Each answer links to the primary source it was checked against.

Official sources checked

Every answer above was written against a primary source and verified independently. These are the 7 sources behind this set.

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