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

This is a reference page. Its only job is to reproduce accurately, and with attribution, the pharmacokinetic statements that appear in the FDA-approved United States prescribing information for Wegovy, so that somebody keeping a personal medication record can see the provenance of the numbers they run into elsewhere.

It is not medical advice. It has not been written or reviewed by a clinician, and it makes no recommendation about whether any medication suits anybody. It does not tell you how much to take, when to take it, or when to change anything. Those decisions belong to the person who prescribed your medication and who can see your individual situation, which a web page cannot.

If what you want is guidance rather than reference material, the right next step is your prescriber or pharmacist, not a page like this one.

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

The copy consulted was read on 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 2017.

One feature of the current label is worth flagging because it confuses people: the injection and the oral tablet now share a single prescribing information document. They do not share pharmacokinetics. This page describes the injection. The tablet's absorption figures are entirely different and are covered separately.

Labels are revised. The version you read next year may differ from the version quoted here, which is why the access date is printed beside the figures rather than buried in a footer. If a number here ever conflicts with the current label, the current label wins.

Section 12.3 states an absolute bioavailability of 89% following subcutaneous administration.

Absolute bioavailability is the fraction of an administered dose that reaches systemic circulation unchanged, measured against an intravenous reference. A figure of 89% is high, and it is characteristic of a subcutaneous peptide engineered for slow and near-complete absorption from the injection site.

This is the number that makes milligram-for-milligram comparison between injected and oral semaglutide meaningless. The same molecule delivered by two routes produces systemic exposures that differ by roughly two orders of magnitude, and the difference is absorption, not potency. Any comparison that skips over bioavailability will be wrong by a very large multiple.

The label states that maximum concentration of semaglutide is reached 1 to 3 days post dose.

The shape of that statement matters. The label gives a window measured in days, not a point estimate measured in hours. Reference tables and tracking tools routinely convert it into a single figure — 48 hours is the usual choice, being the middle of the range — and that conversion is a modelling decision made by whoever built the table. It is not something the FDA-approved label asserts.

So when you meet a precise time-to-peak value for semaglutide anywhere, including inside an app, the honest description is "a working midpoint drawn from a labeled range of 1 to 3 days". Treating it as a measured property of your own body would be a mistake.

Section 12.3 gives an elimination half-life of approximately 1 week.

Half-life describes the time taken for concentration to fall by half. It does not describe when a medication is gone, and the gap between those two ideas is where most misunderstanding lives. Repeated halvings approach zero slowly, which is why the semaglutide labels describe the molecule as remaining in the circulation for weeks rather than days after a final dose.

The same property explains why levels build across the first several doses rather than resetting between them. For somebody keeping records this is the single most useful fact on the page: what you feel in a given week is not a clean readout of the dose you took that week. It reflects an accumulated level that several previous weeks contributed to.

Wegovy 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 because the information is secret — it sits in a public document anybody can read — but because a titration schedule is only meaningful attached to a specific person, and a page that publishes one invites readers to follow it. Escalation timing gets individualised constantly: for tolerability, for interactions with other medications, for clinical circumstances no reference page can know about.

The honest framing is the one used throughout this pillar. A stepwise schedule exists. It is defined in the label and individualised by your prescriber. Your job, and the job of a tracking app, is to record accurately what was actually prescribed and actually taken — never to generate a plan.

GLP-1 Tracker treats a medication like Wegovy as a record-keeping problem, which is the only kind of problem an app is qualified to solve here.

What it records is what you enter: the date of each dose you log, 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 any notes you want to keep about how a week went. It holds those together in one timeline instead of scattered across a notes app, a paper diary and memory.

What it 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. The value is entirely in having an accurate, complete record when somebody qualified asks what has actually been happening.

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

It is a teaching illustration and nothing more. It is built from population-level label figures, not from you. It cannot account for your body weight, your kidney function, injection-site variation, adherence gaps, or the ordinary biological variability between two people given identical doses. It is not a measurement, it is not a blood level, and it is not a clinical reading.

The legitimate use of a curve like that is intuition: seeing why a weekly medication accumulates over the first month, or why a missed dose does not produce an immediate cliff. The illegitimate use is treating it as information about your own body, or letting it influence a dose. It should never do either.