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Missed Dose Guidance Timing Calculator

Work out missed dose guidance timing instantly with clear inputs, formula shown and shareable results.

About Missed Dose Guidance Timing Calculator

Applies the common half-interval rule for a missed dose and shows how long remains until the next scheduled dose.

Formula

Half-interval rule

If less than half the dosing interval has elapsed, take the missed dose; otherwise skip it and resume the schedule

Worked example

With the default values below, Missed Dose Guidance Timing Calculator returns General guidance of Less than half the interval has passed — the usual advice is to take the dose now and keep the normal schedule. Change any input above and every figure here is recalculated in your browser.

Inputs used

Usual interval between dosesaccepts 1–48 h
12 h
Hours since the dose was dueaccepts 0–48 h
3 h

Results

General guidance
Less than half the interval has passed — the usual advice is to take the dose now and keep the normal schedule
Share of the interval elapsed
25.0%
Hours until the next scheduled dose
9.00 h

Step by step

  1. 1Values used
  2. 2Half-interval rule
  3. 3General guidance= Less than half the interval has passed — the usual advice is to take the dose now and keep the normal schedule
  4. 4Share of the interval elapsed= 25.0
  5. 5Hours until the next scheduled dose= 9.00 h

Assumptions and limits

  • The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
  • Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
  • Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.

Frequently Asked Questions

Does the rule apply to every medicine?

No. Oral contraceptives, anticoagulants, antiepileptics and insulin all have specific missed-dose instructions.

Why never double the dose?

Doubling produces a peak concentration the medicine was never designed to deliver and can cause toxicity.

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Missed Dose Guidance Timing Calculator | Calcrivo