CPhT PTCE Release Date

Needlegauge (G)refers to thediameter of the needle’s lumen(opening).The higher the gauge number, the smaller the needle diameter.

Lower gauge (e.g., 13G, 18G)→Larger needle(wider opening)

Higher gauge (e.g., 27G)→Smaller needle(narrower opening)

Common Needle Gauges and Their Uses:Gauge (G)

Needle Diameter (mm)

Common Use

13G

2.4 mm

IV drug administration (large-bore)

18G

1.2 mm

Drawing thick medications (e.g., oil-based injections)

20G

0.9 mm

General intramuscular (IM) injections

27G

0.4 mm

Subcutaneous (SC) or intradermal (ID) injections (e.g., insulin, vaccines)

Since27Gis the highest gauge listed, it corresponds to thesmallestneedle diameter, making it the correct answer.

A. 13G❌→ One of the largest gauges, used for IV fluids or blood transfusions.

B. 18G❌→ Large needle used for thick medications likedepot injections or contrast agents.

C. 20G❌→ Common forintramuscular injectionsbut larger than 27G.

PTCB PTCE Exam Content Outline– Covers needle gauges, injection routes, and proper medication administration.

USP <797> & USP <800>– Provide sterile compounding guidelines, including appropriate needle gauge selection.

CDC Vaccine Administration Guidelines– Recommend25-30Gfor subcutaneous and intradermal injections.

Why Not the Other Options?Key References:

When entering prescription information into a pharmacy computer system,using leading zeros helps prevent medication dosing errorsby clearly specifying the correct dose.

What Are Leading Zeros?Aleading zerois azero placed before a decimal pointto prevent misinterpretation.

✅Correct:0.5 mg(clearly means half a milligram)

❌Incorrect:.5 mg(could be mistaken for 5 mg, leading to a10× overdose).

A. Allergies❌→Important, butnot directly related to dosing errors.

C. Insurance Information❌→Unrelated to medication dosing safety.

D. Contraindications❌→Relevant to medication selection, but not specific to preventing dosing errors.

ISMP Best Practices for Medication Safety– Recommends usingleading zerosto prevent dosing mistakes.

Joint Commission "Do Not Use" List– Warns against missing leading zeros in prescriptions.

PTCB PTCE Exam Content Outline– Covers prescription entry and error prevention strategies.

Why Not the Other Options?Key References:

ISMP’s “Do Not Use” / error-prone abbreviations and dose designations emphasize avoiding trailing zeros (e.g., “120.0 mcg”), because the decimal point can be overlooked, potentially causing a tenfold error (e.g., read as 1200 mcg). ISMP also recommends using a leading zero before a decimal (e.g., 0.2 mg) to prevent misreads; thus 0.2 mg (A) and 1.4 mg (D) adhere to that guidance. 300 mcg (B) uses an acceptable unit (“mcg” rather than “µg”). Therefore, “120.0 mcg” (C) is the most error-prone due to the trailing zero.

References (Pharmacy Technician documents / Study Guides):

• ISMP Error-Prone Abbreviations, Symbols, and Dose Designations list: avoid trailing zeros; always use a leading zero before a decimal.

• PTCB/ExCPT medication safety sections covering safe dose expressions and ISMP recommendations.

• NCC MERP/ISMP educational materials on decimal point misinterpretation and tenfold dosing errors.

Escitalopram (Lexapro)is aselective serotonin reuptake inhibitor (SSRI)used formajor depressive disorder (MDD) and generalized anxiety disorder (GAD). If escitalopram isnon-formulary, a suitable alternative would besertraline (Zoloft), anotherSSRIwith a similar mechanism of action and indication.

A. Cabergoline→ Incorrect; cabergoline is adopamine agonistused to treathyperprolactinemia, not depression or anxiety.

B. Ciprofloxacin→ Incorrect; ciprofloxacin is afluoroquinolone antibiotic, unrelated to antidepressant therapy.

D. Amantadine→ Incorrect; amantadine is anantiviral and antiparkinsonianagent, not used for depression.

Other Answer Choices Explained:References:

PTCB PTCE Exam Content Outline (Pharmacology for Technicians – Nervous System Drugs)

Lexicomp Drug Monographs for SSRIs (Escitalopram & Sertraline)

Goodman & Gilman’s The Pharmacological Basis of Therapeutics