1. What is Days Supply Calculation?

Days supply calculation is a fundamental pharmacy technique used to determine how long a medication supply will last based on the total quantity dispensed and the prescribed daily dosage.

2. How Does the Calculator Work?

The calculator uses the days supply formula:

Where:

• \( DS \) — Days supply (days)
• \( TQ \) — Total quantity (units)
• \( DD \) — Daily dose (units/day)

Explanation: The formula divides the total quantity of medication by the daily dosage to determine how many days the supply will last.

3. Importance of Days Supply Calculation

Details: Accurate days supply calculation is crucial for proper medication management, insurance billing, refill scheduling, and ensuring patients have adequate medication supply between refills.

4. Using the Calculator

Tips: Enter total quantity in units and daily dose in units per day. Both values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What units should I use for calculation?
A: Use consistent units for both total quantity and daily dose (e.g., tablets, mL, mg). The calculator will output days supply in days.

Q2: How do I handle PRN medications?
A: For PRN (as needed) medications, use the maximum expected daily usage rather than the prescribed frequency for accurate days supply calculation.

Q3: What about medications with multiple daily doses?
A: Calculate the total daily dose by multiplying the dose per administration by the number of administrations per day.

Q4: How should I round the result?
A: Typically round to the nearest whole day, though specific rounding rules may vary by pharmacy policy or insurance requirements.

Q5: Are there exceptions to this formula?
A: Some medications (like insulin, inhalers, or topical preparations) may require special calculations based on specific usage patterns or delivery devices.