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Half-life visualizer

Pick a compound, a dose, and how often you take it. You'll see the level rise as each dose absorbs and fall as it clears — and where it settles once you've been dosing for a while (the "steady state").

Runs entirely in your browser — nothing is sent anywhere.

Dosing for
00.861 mgDay 0Day 21Day 42Day 63Day 83

Steady-state peak

0.798 mg

Half-life

6.9 days

Reaches steady state

~5 weeks

Accumulation

1.98×

Solid = while you're dosing; dashed = projected clearance after the last dose. The curve rises as each dose absorbs, then falls — and climbs over the first several doses until it settles into a steady peak-and-trough.

See full detail and FAQ for Semaglutide

How the curve works

An injection doesn't hit its peak instantly — it absorbs over time, so the level rises to a peak and then falls. Each dose also adds to whatever is left from the doses before it, so with weekly medications like the GLP-1s, levels climb over the first several doses and then settle into a repeating peak-and-trough pattern — that's steady state. It's why the early weeks feel different from later ones, and why agradual titrationgives your body time to adjust.

The accumulation figure is how much higher the steady-state peak is than a single dose alone. This is a simplified one-compartment model with first-order absorption; the built-in half-life values are approximate (well-characterized for the GLP-1s, rougher for peptides), and your own numbers vary — pick Custom to enter your own.

Half-life by compound

Pick a compound for its half-life & steady state

This is an educational model, not medical advice or a guarantee of how any compound behaves in your body. Follow the guidance of a qualified healthcare provider.

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