PTCB Patient Safety and Quality Assurance
Updated October 27, 2026
Patient Safety and Quality Assurance is 23.75% of the PTCE. It’s about preventing medication errors: recognizing drugs that are easy to confuse, avoiding dangerous abbreviations, handling high-alert medications carefully and reporting errors. Here’s what to know, followed by free practice questions.
Look-alike, sound-alike drugs and tall man lettering
Some drug names look or sound alike, and mixing them up can harm patients. Tall man lettering uses capital letters to highlight the part of the name that differs:
| Pair |
|---|
| hydrOXYzine and hydrALAZINE |
| predniSONE and prednisoLONE |
| ALPRAZolam and LORazepam |
| glipiZIDE and glyBURIDE |
Abbreviations to avoid
The Joint Commission’s “Do Not Use” list includes:
| Don’t use | Problem | Write instead |
|---|---|---|
| U | Mistaken for 0 or 4 | “unit” |
| IU | Mistaken for IV or 10 | “international unit” |
| Q.D., Q.O.D. | Mistaken for each other | “daily”, “every other day” |
| Trailing zero (5.0 mg) | Decimal point missed: read as 50 mg | 5 mg |
| No leading zero (.5 mg) | Decimal point missed: read as 5 mg | 0.5 mg |
| MS, MSO4, MgSO4 | Morphine and magnesium sulfate confused | Write the full drug name |
High-alert medications
Some drugs cause serious harm when used in error, so extra checks are used. Common examples include insulin, anticoagulants such as heparin and warfarin, opioids, and concentrated electrolytes such as potassium chloride.
Free PTCB patient safety practice questions
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A prescription is written for "Coumadin 5.0 mg." What is the safety problem?Answer: DTrailing zeros are on the "Do Not Use" list because the decimal point can be missed, turning 5.0 mg into 50 mg. Write "5 mg."
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Why is "U" on the Do Not Use list?Answer: AA handwritten "U" for units can be misread as 0 or 4, causing a tenfold or larger overdose. Write out "unit."
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What is the purpose of tall man lettering, as in hydrOXYzine and hydrALAZINE?Answer: BCapitalizing the differing letters helps people notice the difference between names that look alike, reducing selection errors.
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Which is considered a high-alert medication?Answer: CInsulin is a high-alert medication: dosing errors can cause severe low or high blood sugar. Extra checks are used when preparing and dispensing it.
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How should a dose of half a milligram be written?Answer: BAlways use a leading zero for doses less than 1, as in 0.5 mg, and no trailing zero. ".5 mg" can be misread as 5 mg.
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A technician notices that a filled prescription contains predniSONE instead of the prescribed prednisoLONE. What should happen first?Answer: DPrednisone and prednisolone are different drugs. Fix the error before it reaches the patient and report it through the pharmacy's process, so the cause can be addressed.
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Which FDA program is used to report serious adverse drug reactions and product problems?Answer: BMedWatch is the FDA's program for reporting serious adverse events and product problems. Vaccine adverse events go to VAERS.
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Why should a counting tray be cleaned after counting sulfa drugs or penicillins?Answer: CResidue from drugs that commonly cause allergies, such as penicillins and sulfonamides, can contaminate the next prescription. Clean the tray (often with alcohol) after counting them.
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A prescription is for an extended-release tablet, and the patient asks if they can crush it. What is the concern?Answer: DCrushing an extended-release or enteric-coated product can release the full dose too quickly or destroy its coating. Refer the patient to the pharmacist; many products are on "Do Not Crush" lists.
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What is the main purpose of scanning a product's barcode during prescription filling?Answer: ABarcode scanning matches the stock bottle's NDC to the prescription, catching wrong-drug and wrong-strength selection errors.
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Why are look-alike, sound-alike drugs often stored apart on pharmacy shelves?Answer: BSeparating look-alike, sound-alike products, and using shelf alerts or tall man lettering, reduces selection errors.
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Which abbreviation is on the Joint Commission's "Do Not Use" list because it can mean morphine or magnesium sulfate?Answer: C"MS," "MSO4" and "MgSO4" can be confused with each other. Write "morphine sulfate" or "magnesium sulfate" in full.
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A drug utilization review (DUR) alert appears for a possible drug interaction. What should the technician do?Answer: DClinical alerts such as drug interactions and duplicate therapy require the pharmacist's professional judgment. Technicians shouldn't override clinical alerts.
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After a dispensing error reaches a patient, what is the purpose of a root cause analysis?Answer: AA root cause analysis looks at the processes that allowed the error, not just the person involved, so the pharmacy can change its systems and prevent it from happening again.
Pass the PTCB exam on your first try
- All 194 questions across medications, federal requirements, patient safety and order entry
- An explanation for every answer, with the law, standard or label behind it
- Unlimited full 90-question practice exams, with each domain in its real share