How this calculator works
Around-the-clock spacing divides 24 hours by the prescribed daily count. Waking-interval mode divides the time from first to last by one fewer than the dose count, leaving a different overnight gap. The two conventions can give different schedules. A pharmacist or prescriber should clarify which the instructions require, including food, sleep and missed-dose guidance. The result is an estimate for information only and is not medical advice.
Formula
Around the clock: interval = 24/doses per day. Waking interval: spacing = (last time - first time, advancing to next day when needed)/(doses - 1). Overnight gap = 24 - spacing x (doses - 1).
Worked example
Three equally spaced doses starting at 08:00 give 08:00, 16:00 and 00:00 next day. Three doses between 08:00 and 20:00 give 08:00, 14:00 and 20:00, followed by a 12-hour gap.
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Frequently asked questions
Does three times daily always mean every eight hours?
Instructions vary. The form shows both arithmetic conventions; confirm the intended one rather than changing your prescription.
What does day offset 1 mean?
That clock time occurs on the day after the first dose in the displayed example.
Does it handle missed doses or daylight saving?
No. It is a clock-layout tool without dates, drug-specific instructions or daylight-saving adjustments.