Certified Medical Assistant (CMA AAMA)PharmacologyMedium
A physician orders phenobarbital 60 mg PO daily for a patient. The pharmacy dispenses phenobarbital 15 mg tablets. How many tablets should the medical assistant administer per dose?
- A2 tablets
- B4 tablets
- C1 tablet
- D3 tablets
Show answer & explanationAnswer & explanation
Correct answer: B. 4 tablets
To calculate the number of tablets, divide the ordered dose by the dose per tablet: 60 mg (ordered) / 15 mg/tablet (on hand) = 4 tablets.
Why the other options are wrong
- A. 2 tablets would be 30 mg, which is an underdose.
- C. 1 tablet would only be 15 mg, which is an underdose.
- D. 3 tablets would be 45 mg, which is an underdose.
Tablet Dosage Calculation
To calculate the number of tablets, divide the desired dose by the dose available per tablet.
- Formula: (Desired Dose / Available Dose) = Number of Tablets.
- Ensure units are consistent.
- Double-check calculations to prevent medication errors.
Memory trick: Desired Over Have, that's how you get your Tab.