ATI TEAS (Test of Essential Academic Skills) Version 7MathematicsHard

A patient is given a prescription for a pain reliever to be taken every 4 to 6 hours as needed. If the patient took the first dose at 08:00 on Monday, what is the earliest time on Tuesday they could take their fifth dose?

  1. A00:00 Tuesday
  2. B04:00 Tuesday
  3. C08:00 Tuesday
  4. D12:00 Tuesday
Show answer & explanation

Correct answer: B. 04:00 Tuesday

The patient needs 4 doses after the first. To find the earliest time for the 5th dose, we use the shortest interval (4 hours). First dose: 08:00 Mon. Second dose: 08:00 + 4h = 12:00 Mon. Third dose: 12:00 + 4h = 16:00 Mon. Fourth dose: 16:00 + 4h = 20:00 Mon. Fifth dose: 20:00 + 4h = 24:00 Mon (which is 00:00 Tuesday).

Why the other options are wrong

  • A. This is the earliest time for the fifth dose, considering the shortest interval of 4 hours.
  • C. This assumes a 24-hour interval for each subsequent dose after the first, which is incorrect for 'every 4-6 hours'.
  • D. This is incorrect; it would imply a much longer interval between doses.

Medication Dosing Schedule

The timing and frequency of medication administration based on prescription instructions.

  • 'Every X hours' means the interval between doses.
  • 'As needed' (PRN) allows flexibility within the prescribed interval.
  • Calculating earliest/latest doses requires careful time addition/subtraction.

Memory trick: Dosing times: Start, interval, count doses, track the clock.

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