Half-life gets quoted as though it were a stopwatch for when a substance is
“gone”. It is really the parameter that decides how much stacks up when you
dose again before the last one cleared. This draws that curve so you can see
the shape instead of guessing at it.
⚠This is a teaching model, not a dosing calculator. It plots a
one-compartment textbook model in relative units, with no absolute
concentrations, no route or bioavailability modelling, and no individual
variation. Real pharmacokinetics are non-linear, vary hugely between people,
and cannot be derived from two sliders. Do not use this to plan anything you
put in your body.
Scenarios
Concentration over time
Relative units — both scenarios receive the same dose
Plasma concentration over time
Line chart comparing modelled concentration for two dosing scenarios.
The equivalent numbers are available in the data table below.