The short answer
Longer than most people expect. Semaglutide (Ozempic, Wegovy, Rybelsus) has a half-life of about a week, and its labels say it stays in the blood for about 5 to 7 weeks after the last dose. Tirzepatide (Mounjaro, Zepbound) has a half-life of about 5 days, which works out to roughly a month. The daily pill orforglipron (Foundayo) clears in about 6 to 10 days. The effects fade gradually over that time, not overnight.
At GLP-1 SOS we hear this question at three moments: before a surgery, before trying for a baby, and in the weeks after stopping. The answer comes from one number on each label: the half-life.
From the labels
How long, by medication
Semaglutide: 5 to 7 weeks
Ozempic, Wegovy, Rybelsus and the Wegovy pill. Half-life about 1 week.
Tirzepatide: about a month
Mounjaro and Zepbound. Half-life about 5 days, or 5 to 6 days in people with obesity.
Orforglipron: about a week
The Foundayo pill, taken daily. Half-life 29 to 49 hours.
A drug is mostly gone after about five half-lives, which is how the semaglutide labels reach their numbers. Compounded versions of the same molecule should follow the same clock.
What a half-life means for you
A half-life is the time it takes for half of the drug to leave your blood. One week after your last semaglutide dose, about half is still there; after two weeks, a quarter; after three, an eighth. The Ozempic and Rybelsus labels put the practical end at about 5 weeks, and the Wegovy label at 5 to 7 weeks after the last 2.4 mg or 7.2 mg shot or 25 mg pill. The tirzepatide labels give the half-life but no clearance time; the same arithmetic gives roughly 25 to 30 days. Orforglipron’s half-life is 29 to 49 hours, so most of it is gone within about 6 to 10 days. It is the same slow curve that shapes how long nausea lasts after each shot.
Lab note
Half left after one half-life, mostly gone after five. That is the whole clock.
The effects fade along that curve, not off a cliff. Appetite and food noise usually creep back over weeks, which is why many people feel fine at first and surprised a month later. In the STEP 1 trial extension, people who stopped semaglutide 2.4 mg after 68 weeks had regained 11.6 of the 17.3 percentage points of body weight they had lost one year later. More on why food noise comes back.
The clock also matters for three decisions. Pregnancy: the semaglutide labels say to stop at least 2 months before a planned pregnancy. Surgery: the labels warn that a slow stomach can hold food even after normal fasting, and a 2024 guidance from five medical societies says many people can stay on the medication, with a liquid-only diet for 24 hours beforehand when the risk is higher. Restarting: the Wegovy label says that after 2 or more missed weekly doses, the dose is built up again from a lower step.
From the labels and trials
The numbers behind the clock
About half
of a semaglutide dose is still in your blood one week later, per its 1-week half-life
5 to 7 weeks
semaglutide stays in circulation after the last Wegovy dose, per the Wegovy label
2 months
to stop semaglutide before a planned pregnancy, per the Wegovy and Ozempic labels
Sources: Wegovy Prescribing Information, June 2026; Ozempic Prescribing Information, May 2026; Zepbound Prescribing Information, August 2026; Foundayo Prescribing Information, July 2026.
What to do with this
- Planning a pregnancy? Start the conversation early. On semaglutide, the labels say to stop at least 2 months ahead. On Zepbound or Mounjaro with the birth control pill, use a backup method for 4 weeks after starting and after each dose increase.
- Before any surgery or scope, tell the team. Give the name, dose and day of your last dose, and follow their instructions on food and liquids. Do not stop on your own unless they ask you to.
- Stopping? Plan it with your prescriber. Expect appetite to return over weeks, not days, and decide in advance what meals, protein and movement will look like when it does.
- Restarting after a break? Ask about the dose. Going straight back to your old dose after weeks off can feel like a big dose increase. Ask your prescriber where to restart.
- Keep your gut routine steady through the change. Bowel habits can shift for a while as the medication wears off; here is why your gut can feel off after quitting. A steady evening routine helps, and GLP-1 SOS Daily Gut Relief, 2 capsules with dinner, supports regular bowel movements and digestive comfort on or off the medication.*
- Look past the window. If a symptom starts or keeps building well after the drug should be gone, it is less likely to be the medication. Get it checked rather than waiting it out.
*GLP-1 SOS Daily Gut Relief supports regular bowel movements and digestive comfort. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
Two kinds
Normal while it clears, or a call
Usually expected
- Appetite returning slowly over several weeks
- Side effects easing week by week
- Food noise coming back gradually
- Bowel habits shifting as things settle
Call your prescriber
- A positive pregnancy test while it may still be in your system
- Severe belly pain, with or without vomiting
- Vomiting, or not keeping liquids down
- Symptoms still building well after the clearance window
The medication leaves slowly. Plan stops, surgeries and pregnancies around its clock.
When to call your doctor
Call your prescriber, or tell your care team, if:
- You have a positive pregnancy test while on the medication or within the clearance window
- You have surgery, a scope or sedation coming up
- You have severe or lasting belly pain, sometimes spreading to your back
- You are vomiting or cannot keep liquids down
- You have upper right belly pain with fever or yellow skin or eyes
- You want to restart after a break of two weeks or more
The drug leaves slowly. Plan the stop, the surgery or the pregnancy with your prescriber, not around it.
From the people behind the Lab
You do not have to figure this out alone.
GLP-1 SOS is the daily companion made for life on a GLP-1. Plain answers like this one, a support team that replies to real questions from real people, and daily formulas like GLP-1 SOS Daily Gut Relief, designed around the side effects that come with the medication. The GLP-1 Lab is our free education arm: no login, no paywall, no hype. Side effects are part of the road. Suffering through them is not.
Questions people also ask
How long does Ozempic stay in your system?
About 5 weeks after the last dose, per the Ozempic label. Semaglutide has a half-life of about a week, so roughly half is still in your blood seven days after your last shot. At the higher Wegovy doses, the label says about 5 to 7 weeks. The effects fade gradually over that time rather than stopping at once.
How long do Mounjaro and Zepbound stay in your system?
Roughly a month. Tirzepatide has a half-life of about 5 days, or 5 to 6 days in people with obesity per the Zepbound label. The labels do not state a clearance time, but about five half-lives works out to 25 to 30 days. If you use the birth control pill, the labels advise a backup method for 4 weeks after starting and each dose increase.
Do I need to stop my GLP-1 before surgery?
Not always, and not on your own. The labels say data are insufficient to set a rule and ask you to tell your surgical team you take one. A 2024 guidance from five medical societies says many people can continue, with a liquid-only diet for 24 hours before the procedure when there is concern. Follow your surgeon and anesthesia team.
How long after stopping Wegovy can I get pregnant?
The Wegovy and Ozempic labels say to stop at least 2 months before a planned pregnancy, because semaglutide takes 5 to 7 weeks to clear. For tirzepatide, the Zepbound label says to stop when a pregnancy is recognized and to use backup birth control with the pill. Plan the timing with your prescriber before you stop.
Does compounded semaglutide stay in your system as long?
If it contains the same molecule, it should follow the same clock: a half-life of about a week and roughly 5 to 7 weeks to clear. Compounded products are not FDA-approved, so their labels and quality can vary. The daily pill orforglipron (Foundayo) is different: its half-life is 29 to 49 hours, so it clears in about 6 to 10 days.
Sources (7)
- Wegovy (semaglutide) injection and tablets, Prescribing Information. Novo Nordisk / FDA, revised June 2026.
- Ozempic (semaglutide) injection, Prescribing Information. Novo Nordisk, revised May 2026.
- Rybelsus and Ozempic (semaglutide) tablets, Prescribing Information. Novo Nordisk, revised January 2026.
- Zepbound (tirzepatide) injection, Prescribing Information. Eli Lilly, revised August 2026.
- Foundayo (orforglipron) tablets, Prescribing Information. Eli Lilly, revised July 2026.
- Wilding JPH, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes, Obesity and Metabolism, 2022.
- Kindel TL, et al. Multi-society clinical practice guidance for the safe use of glucagon-like peptide-1 receptor agonists in the perioperative period. Surgical Endoscopy, 2025.
Reviewed by the GLP-1 SOS editorial team · Education, not medical advice · Talk to your prescriber about your dose and your symptoms.
