Question 1
A patient presents the following prescription:
Amoxicillin 250 mg/5 mL
1 tsp tid x 10 days
How much of the medication, in mL, will be used during the first 5 days of therapy?
- AOption A:
25
- BOption B:
50.
- COption C:
75.
- DOption D:
150.
Show answer and explanation
Correct answer: C
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