Saxenda Half-Life and Pharmacokinetics, Straight From the FDA Label

This is a reference page. Its job is to reproduce, accurately and with attribution, the pharmacokinetic statements in the FDA-approved United States prescribing information for Saxenda, so somebody keeping a personal record can see the provenance of the numbers they encounter.

It is not medical advice. It has not been written or reviewed by a clinician, and it makes no recommendation about whether any medication is appropriate for anybody. It does not tell you how much to take, when to take it, or what to do about a dose you did not take.

If what you want is guidance rather than reference material, that conversation belongs with your prescriber or pharmacist.

All figures on this page come from one document: SAXENDA (liraglutide) injection, for subcutaneous use — the United States Prescribing Information approved by the FDA. The pharmacokinetic statements sit in Section 12.3, Pharmacokinetics.

The copy consulted was read via FDA accessdata and DailyMed, the National Library of Medicine's mirror of current FDA-approved labeling, accessed 1 September 2026. The label records an Initial U.S. Approval of 2010.

Liraglutide is marketed under two brand names with different indications, and both labels are separate documents. They agree on half-life and on bioavailability. They do not phrase time to peak identically, which is the subject of its own section below because it is the kind of detail that gets flattened in secondary sources.

This is the most useful thing on the page, and it is a small thing.

The Saxenda label states that maximum concentrations of liraglutide are achieved at 11 hours post dosing. The Victoza label states that maximum concentration is reached 8 to 12 hours post dosing. Those are different statements: one a specific value, the other a window.

A reference table that carries a single "liraglutide" row has to choose, and in practice many choose the midpoint of the Victoza range — 10 hours — or carry a figure derived from one label under both product names. Neither is what the Saxenda label says.

This page gives 11 hours for Saxenda because 11 hours is what the Saxenda label states, not a figure carried over from the Victoza range.

Section 12.3 states a plasma half-life of 13 hours after subcutaneous administration.

Against the rest of this class that is the short end by a wide margin — semaglutide's labeled figure is approximately one week, tirzepatide's approximately five days. Thirteen hours is a different pharmacological regime, and the daily dosing schedule follows directly from it: concentration falls substantially between one dose and the next rather than persisting at a plateau.

It also means a gap in dosing behaves differently than it would for a weekly agent, where a missed dose sits on top of a large residual level. What that implies for any individual is a question for a prescriber or pharmacist, and this page does not answer it.

The label states an absolute bioavailability of approximately 55% following subcutaneous administration — roughly half of an administered dose reaching systemic circulation, against 80% for tirzepatide and 89% for semaglutide on their labels.

Section 12.3 also reports that liraglutide is extensively bound to plasma protein, greater than 98%, and gives a mean apparent volume of distribution after subcutaneous administration of 20 to 25 L for a person weighing approximately 100 kg.

Those last figures are included because they are labeled values and this pillar publishes labeled values. They are not figures a person keeping a personal record needs to act on, and no page should imply otherwise. They describe how the molecule distributes in the body, which is background rather than anything actionable.

Liraglutide is escalated gradually rather than started at a maintenance level, and the prescribing information describes that escalation in its dosage and administration section.

This page does not reproduce it — not the steps, not the intervals, not the conditions for moving between them. A titration schedule is only meaningful attached to a specific person, and publishing one invites readers to follow it rather than the plan they were actually given.

A stepwise schedule exists, it is defined in the label, and it is applied to you by your prescriber. The job of a record is to capture accurately what was prescribed and what was taken.

GLP-1 Tracker records what you enter: the days you logged a dose, the injection site you noted, weight and BMI entries added over time, meals captured through the photo scan with calories, protein and fiber estimated, and notes about how a stretch of days went.

For a daily injectable the valuable thing is continuity. A run of consecutive days is what makes a pattern visible; a handful of isolated entries is not, and it is not much use to a clinician either.

What the app does not do is decide anything. It does not evaluate whether your routine is working, it does not flag anything as clinically significant, and it does not generate schedules or advise on gaps.

GLP-1 Tracker includes an educational medication-level view that draws a curve from logged doses and a published half-life figure of the kind quoted on this page.

For a daily medication with a 13-hour half-life the curve shows pronounced peaks and troughs rather than the smooth plateau the weekly agents produce, and that contrast is genuinely instructive about why the dosing intervals differ across this class.

It is still a teaching illustration built from population figures rather than from you. It cannot account for your body weight, your kidney function, injection-site variation or ordinary biological variability between people given identical doses. It is not a measurement, not a blood level, and not a clinical reading.