CPhT PTCE Exam Questions and Answers PDF

To calculate how muchamoxicillin suspensionwill be used in the first5 days, we follow these steps:

Amoxicillin concentration:250 mg per5 mL

Dosage:1 tsp (5 mL) three times daily (tid)

Duration:First5 days

Step 1: Identify Given InformationStep 2: Calculate Total Daily Volume5 mL×3=15 mL per day5 \text{ mL} \times 3 = 15 \text{ mL per day}5 mL×3=15 mL per day

Step 3: Multiply by 5 Days15 mL/day×5 days=75 mL15 \text{ mL/day} \times 5 \text{ days} = 75 \text{ mL}15 mL/day×5 days=75 mL

Thus, the patient will use75 mLof medication in the first5 days.

A. 25 mL→ Incorrect; this would be correct if taken onlyonce dailyinstead ofthree times daily.

B. 50 mL→ Incorrect; this is the correct amount for3.3 days, not 5 days.

D. 150 mL→ Incorrect; this is thefull 10-day course, not just the first 5 days.

Other Answer Choices Explained:References:

PTCB PTCE Exam Content Outline (Pharmaceutical Calculations – Dosage & Volume Calculations)

USP <795> Nonsterile Compounding Guidelines

Lexicomp Drug Monograph for Amoxicillin Suspension

To determine the correct volume of amoxicillin suspension per dose, use the given concentration and dose.

Prescription dose:150 mg per dose

Suspension concentration:250 mg per 5 mL

Formula to calculate volume needed:Volume (mL)=Prescribed dose (mg)Concentration (mg/mL)\text{Volume (mL)} = \frac{\text{Prescribed dose (mg)}}{\text{Concentration (mg/mL)}}Volume (mL)=Concentration (mg/mL)Prescribed dose (mg)​

Step 1: Identify Given InformationStep 2: Calculate150 mg250 mg/5 mL=150×5250=750250=3 mL\frac{150 \text{ mg}}{250 \text{ mg/5 mL}} = \frac{150 \times 5}{250} = \frac{750}{250} = 3 \text{ mL}250 mg/5 mL150 mg​=250150×5​=250750​=3 mL

Thus, the patient should take3 mL per dose.

B. 4 mL→ Incorrect; this would correspond to a different strength.

C. 5 mL→ Incorrect; this would deliver250 mg, which is incorrect.

D. 6 mL→ Incorrect; this would deliver300 mg, exceeding the prescribed dose.

Other Answer Choices Explained:References:

PTCB PTCE Exam Content Outline (Pharmaceutical Calculations – Dosage & Volume Calculations)

USP <795> Guidelines for Nonsterile Compounding & Drug Dilution

Lexicomp Drug Monograph for Amoxicillin Suspension