How Long Does Wegovy Stay in Your System? Half-Life, Weeks to Clear and What It Means

Written by Diana Gangan. Updated November 3, 2026.

Wegovy stays in your system for about 5 to 7 weeks after your last dose, according to the official US prescribing information. The reason is its long half-life: semaglutide, the active ingredient in Wegovy, has a half-life of about one week, which means the amount in your blood falls by roughly half every seven days. After one week about 50% is left, after two weeks about 25%, and after five weeks only about 3%. The same 5 to 7 week window applies to the 2.4 mg weekly injection, the higher 7.2 mg dose (Wegovy HD) and the 25 mg daily Wegovy pill. This long tail is why the label tells women to stop Wegovy at least 2 months before a planned pregnancy, and why you should tell your surgical team you take it. This guide shows the week-by-week math, compares the shot with the pill, and explains what the clearance time means for side effects, weight, surgery, missed doses and drug tests, as of November 2026.

A drug's half-life is the time it takes for the amount in your blood to drop by half. The Wegovy label gives semaglutide an elimination half-life of "approximately 1 week." A pharmacokinetic study by Ikushima and colleagues in 2018 measured a steady-state half-life of 145 to 167 hours, which is about 6 to 7 days. That is very long for a medicine, and it is what allows the injection to be given only once a week.

The half-life is the same whether you use the injection or the pill, because both contain the same molecule. It is also the same molecule as Ozempic, so the two clear the body at the same rate; the differences between those brands are covered in Wegovy vs Ozempic.

The label states that semaglutide is "present in the circulation for about 5 to 7 weeks" after the last dose of the 2.4 mg or 7.2 mg injection or the 25 mg tablet. You can check that figure with simple arithmetic. Pharmacologists usually treat a drug as essentially gone after about five half-lives. Five half-lives of about 7 days each is about 35 days, or 5 weeks. Halving five times leaves about 3% of the starting amount (one half, times one half, five times over, is 1/32). Seven half-lives, about 49 days, leaves less than 1%.

The table below applies that halving to the average steady-state blood levels in the label: about 75 nmol/L on 2.4 mg, about 230 nmol/L on 7.2 mg and about 77 nmol/L on the 25 mg pill. Each week, the previous week's number is divided by two. The figures are rounded and simplified; real levels vary from person to person and depend on when in the dosing week you stopped.

The 7.2 mg dose starts about three times higher, so it takes roughly one to two extra half-lives to reach the same absolute level as 2.4 mg, though the label gives the same 5 to 7 week range. The biggest drop comes early: three quarters of the drug is gone after two weeks.

No. The FDA approved Wegovy tablets on December 22, 2025, and Novo Nordisk announced FDA approval of Wegovy HD 7.2 mg on March 19, 2026, for adults who had tolerated 2.4 mg for at least 4 weeks. The current US label, revised in June 2026, covers all of them. The pill is absorbed very differently: only about 1% to 2% of each tablet reaches the bloodstream, compared with about 89% of an injection, which is why the pill dose (25 mg) is so much larger. But once semaglutide is in the blood, it behaves the same way, with the same half-life of about one week. The practical differences are summarised below and in more depth in Wegovy pill vs injection.

Yes, up to a point. Because each new dose arrives before the previous one has cleared, levels rise over the first few weeks and then level off at a plateau called steady state. An FDA review of the pill found steady state is reached after 4 to 5 weeks of daily dosing. For the weekly injection the same timeline follows from the one-week half-life, though the exact label wording for the injection was not available to us. Building to steady state is separate from the gradual dose increases on the starting schedule, which are explained in the Wegovy dosing schedule. It is one reason the full effect takes time, as covered in how long Wegovy takes to work.

No study we found measured exactly when appetite returns after the last dose, and claims of a specific number of days are not backed by primary data. What the half-life tells us is that drug levels fall to about half in the first week and a quarter by the end of the second week, so most people would expect the appetite-suppressing effect to fade gradually over the first few weeks rather than stop suddenly.

There is no primary data on exactly how long nausea, constipation and other stomach side effects last after the last dose. Because these effects are linked to drug levels, it is reasonable to expect them to ease as levels fall over the first couple of weeks, but individual experience varies. Side effects that are severe or that persist after stopping, such as ongoing vomiting or severe stomach pain, are a reason to contact a doctor rather than wait. What is known about longer-term effects is summarised in GLP-1 long-term side effects.

Weight tends to come back once the drug has cleared. In the STEP 1 trial extension, 327 adults who had lost 17.3% of their body weight after 68 weeks stopped semaglutide. By week 120 they had regained 11.6 percentage points, leaving them 5.6% below their starting weight; the authors reported they had regained two-thirds of their prior weight loss, and improvements in blood pressure and other heart risk markers moved back towards baseline. In the STEP 4 trial, people who lost 10.6% during a 20-week run-in were split into two groups: those who continued semaglutide lost a further 7.9%, while those switched to placebo regained 6.9% over the next 48 weeks, though they stayed below their original weight. More on this, and on staying on a lower dose, is in what happens when you stop taking Wegovy and the Wegovy maintenance dose.

The US label says to "discontinue WEGOVY at least 2 months before a planned pregnancy because of the long half-life." The UK prescribing information gives the same advice. Two months is a little longer than the 5 to 7 week clearance window, which leaves a margin for individual variation. If you become pregnant while taking Wegovy, contact your doctor. On birth control, the label found no clinically relevant change in levels of a common combined pill (ethinylestradiol with levonorgestrel), and the UK information says Wegovy is not expected to reduce the effectiveness of oral contraceptives. The label does note that slower stomach emptying may affect the absorption of other oral medicines, and the FDA review of the pill found levothyroxine (thyroid hormone) levels rose by 33% when taken with oral semaglutide.

Because semaglutide slows stomach emptying and stays in the body for weeks, there is a risk that food remains in the stomach during anesthesia, which can lead to aspiration (stomach contents entering the lungs). The label tells you to inform your healthcare providers before any planned surgery or procedure. In June 2023 the American Society of Anesthesiologists suggested considering holding a weekly GLP-1 drug for a week before a procedure. Newer multi-society guidance from October 2024 (from the ASA and gastroenterology, bariatric and surgical societies) says most patients should continue their GLP-1. People at higher risk, such as those still increasing their dose, those with stomach symptoms or those on high doses, may be asked to follow a liquid diet for 24 hours beforehand, and elective surgery may be delayed until dose escalation is finished.

Under the US label, if you miss a weekly injection and your next dose is more than 2 days away, take it as soon as possible; if it is less than 2 days away, skip it and resume on your regular day. For the pill, skip the missed dose and take the next one the following day. The UK and EU rule for the injection differs: take a missed dose within 5 days, and skip it if more than 5 days have passed. If you have missed several weeks, levels will have fallen a lot, and you should ask your prescriber how to restart rather than going straight back to your previous dose. Details are in the Wegovy dosing schedule.

Semaglutide is not included on standard drug screening panels. The federal SAMHSA workplace panel tests for substances such as amphetamines, cannabis, cocaine, opioids and PCP, and semaglutide is not among them. That does not mean it is undetectable; a specific laboratory test could measure it, but it is not part of routine employment testing. Questions about drinking while the drug is still in your system are covered in Wegovy and alcohol.

Wegovy has a half-life of about one week, so its level in your blood halves every seven days. About three quarters is gone after two weeks, about 97% after five weeks, and the label says it remains in circulation for about 5 to 7 weeks after the last dose. That applies to the weekly injection, Wegovy HD 7.2 mg and the daily pill alike. The long tail matters most for pregnancy planning, where the label advises stopping at least 2 months ahead, and for surgery, where your care team should know you take it. Weight regain after stopping is common, so talk to your doctor before you stop.

This article is for general information and does not replace advice from your doctor or pharmacist. The STEP trials cited were funded by Novo Nordisk, the maker of Wegovy. The week-by-week table is a simplified estimate based on the label's half-life and average levels, not a measurement.