PSA Prescription Writing 4

Question 1

Why should a 'trailing zero' (e.g., writing '1.0 mg' instead of '1 mg') never appear on a prescription?

Accepted Answer

It can be misread as '10 mg,' causing a tenfold overdose

Answer

It violates DEA regulations for controlled substances

Answer

It confuses the generic and brand name

Answer

It indicates the dose should be divided

Question 2

The abbreviation 'U' for units is on the Institute for Safe Medication Practices (ISMP) 'Do Not Use' list. What dangerous misinterpretation can occur?

Accepted Answer

'U' can be misread as '0,' turning '10 U' into '100'

Answer

'U' is confused with micrograms

Answer

'U' implies the drug must be refrigerated

Answer

'U' is confused with the abbreviation for 'ug'

Question 3

Which error is most likely if a prescriber writes 'QD' ambiguously in a handwritten prescription?

Accepted Answer

Both A and B are plausible misreads depending on handwriting

Answer

It may be read as 'QID' (four times daily), causing fourfold overdose

Answer

It may be read as 'QOD' (every other day), causing underdosing

Answer

It may be confused with 'q4h' (every 4 hours)

Question 4

The abbreviation 'MS' on a prescription is considered dangerous because it is ambiguous. What two drugs does it represent?

Accepted Answer

Morphine sulfate and magnesium sulfate

Answer

Metformin and methotrexate

Answer

Methylphenidate and meperidine sulfate

Answer

Metoprolol succinate and metoprolol sulfate

Question 5

A prescription written for 'warfarin 2.5 mg' is presented, but the prescriber's handwriting makes the dose look like '25 mg.' This is an example of which error type?

Accepted Answer

Wrong dose error due to illegibility

Answer

Wrong drug error

Answer

Wrong route error

Answer

Wrong frequency error

Question 6

When writing a prescription for a drug with a narrow therapeutic index (e.g., digoxin), which practice is most important to prevent dosing errors?

Accepted Answer

Writing the dose in both numbers and words (e.g., '0.125 mg [one hundred twenty-five micrograms]')

Answer

Always using Latin abbreviations for brevity

Answer

Using all capital letters throughout

Answer

Omitting the strength and relying on the pharmacist to determine it

Question 7

Which prescribing practice should be avoided to prevent confusion between micrograms and milligrams?

Accepted Answer

Writing the Greek letter μg for micrograms

Answer

Spelling out 'micrograms' in full

Answer

Using 'mcg' as the abbreviation for micrograms

Answer

Expressing the dose as a decimal of milligrams