Liraglutide Half-Life Calculator
Liraglutide has a half-life of about thirteen hours — an order of magnitude shorter than the weekly GLP-1s, and the reason it is injected daily rather than weekly. This calculator charts what that shorter half-life does to the shape of the curve.
Half-life 13 hours · peaks at 10 hours
Every 24 hours.
Half-life
Left at next dose
Liraglutide (Saxenda, Victoza) · once daily · levels plateau after ~2.7 days
Steady-state peak
1.39 mg
Steady-state trough
0.64 mg
Accumulation
1.4×
At once daily, each dose lands before the previous one has cleared, so levels stack to about 1.4× a single dose before plateauing — roughly 2.7 days in. After the last dose it takes about 2.7 days to clear.
This is a modelled estimate of relative levels from published half-life and time-to-peak figures — not a measured blood concentration. Individual pharmacokinetics vary.
Based on a published Liraglutide half-life of about 13 hours. The chart models RELATIVE levels from a unit dose — enter your own figures to see the shape. It is not a dose recommendation.
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What a 13 hours half-life means in practice
A half-life of 13 hours against once daily dosing means each dose lands before the previous one has gone. That changes the curve in three ways:
1. One half-life
Half the dose is gone after 13 hours. After two half-lives 25% remains, after three 12.5%.
2. What's left at the next dose
Dosing once daily means the next dose lands 24 hours later, with about 28% of the previous one still present.
3. Accumulation and plateau
Those leftovers stack until intake matches elimination — about 1.4× a single dose, reached after roughly 2.7 days (five half-lives).
Worked example
Liraglutide (Saxenda, Victoza) has a half-life of 13 hours. Dosing once daily, the next dose arrives 24 hours later with about 28% of the previous one still on board. Levels therefore stack to roughly 1.4× a single dose before plateauing, which takes about 2.7 days — and after a final dose it takes about the same again to clear.
Why liraglutide is daily and semaglutide is weekly
Both are GLP-1 receptor agonists with fatty-acid modifications that bind albumin and slow elimination. The difference is how far that engineering was taken. Liraglutide's modification extends its duration from minutes to roughly half a day; semaglutide's structural changes push the same principle out to about a week.
The consequence for the curve is a much larger peak-to-trough swing. With a half-life around half the dosing interval, a substantial fraction of each dose clears before the next arrives, so levels oscillate more within each cycle than a weekly compound's do across a week. Accumulation is modest and the plateau arrives within a few days rather than over a month.
It also means clearance is fast. A few days after stopping, liraglutide is essentially gone — a very different proposition from the several weeks a weekly compound takes. See how half-life and dosing interval interact for why the ratio matters more than either number alone.
Frequently asked questions
This calculator is provided for informational and educational purposes only and is not medical advice. Always confirm dosing with a qualified healthcare professional and double-check your own measurements before administering anything.
Built by the Pep AI team.