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Calculating quantity from directions — GPhC CRA MCQ

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EasyDispensingCalculating quantity from directionsGPhC CRA

A pharmacist receives a prescription for phenoxymethylpenicillin 250 mg/5 mL oral solution, 5 mL four times daily for 10 days. The total quantity to be supplied has not been specified on the prescription. What is the most appropriate action?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: D — Calculate and supply sufficient quantity for the course specified in the directions — 200 mL

When the total quantity is not specified on a prescription but sufficient information is available from the dose, frequency, and duration to calculate the total, the pharmacist should supply the quantity needed for the complete course. In this case: 5 mL x 4 times daily x 10 days = 200 mL. This is standard pharmaceutical practice and does not require contacting the prescriber. The pharmacist should use their professional judgement and supply enough for the complete course.

Reference: MEP