How Long Does It Take for Zepbound to Work?

More than a dozen medications are FDA approved for weight loss. Zepbound (tirzepatide) is a once a week, injectable medication that has proven to be very effective in helping with weight loss in people who are considered obese or overweight with at least one other chronic condition. 

Zepbound improves appetite, which can lead to eating fewer calories. It also improves cardiovascular risk factors. With all of these health benefits, you may be wondering how long it takes for Zepbound to work. Let’s take a look at how Zepbound works and when you can expect to see effects from the medication. 

How long does it take for Zepbound to work?

Zepbound can begin to have effects in your body within days to weeks after starting the medication. The first thing you may notice is a decreased appetite — usually within the first couple of weeks. It may take 4 to 6 weeks for any noticeable weight loss to happen though. 

But it’s important to remember that the bulk of Zepbound weight loss happens over time. Studies show that it’s possible to lose up to 21% of your starting body weight after 72 weeks (depending on your dose).

It can take weeks to months to see benefits like an improvement in cardiovascular health. Some effects like improvement in obstructive sleep apnea may take longer, up to a year in some cases.

How quickly do you start losing weight on Zepbound?

Based on clinical trials, most users began losing weight about 4 weeks after starting Zepbound. Studies found that at 4 weeks, the average weight loss was nearly 4% of starting body weight. That means a person with a starting body weight of 250 lbs lost about 10 lbs after 4 weeks on the lowest dose. 

It’s important to keep in mind that the study participants didn’t just take medication alone. They also received nutritional counseling, followed a restricted calorie eating plan, and engaged in 150 minutes of exercise each week.

That being said, about 20% of people are late responders to Zepbound. This means they haven’t lost 5% of their starting body weight by week 12 after starting the medication. The good news is that late responders eventually lose weight if they continue taking the medication. If this happens to you, don’t give up: 90% of late-responders lost at least 5% of their body weight by week 72. 

What can you expect after your first dose of Zepbound?

Within a few days of taking your first Zepbound dose, you may begin to notice that you feel full quicker and from smaller amounts of food. You may also notice that you stay full for longer periods of time. 

You can also expect some side effects like nausea or bowel habit changes after the first dose or after increasing doses. These side effects can usually be managed by avoiding large meals, staying hydrated, and eating foods high in fiber and lean protein. 

After you’ve been on the Zepbound starting dose for about 4 weeks, your prescriber will increase your dose slowly. If you find the early side effects of Zepbound problematic, talk to your prescriber. 

How can you tell if Zepbound is working?

Many people don’t notice weight loss right away, and it may leave you questioning whether Zepbound is working. Some of the early effects of the medication and signs that Zepbound is working include:

• Decreased hunger

• Feeling more full

• Less cravings

• Eating smaller portions of food

Some people may also notice changes in other health markers, like improvements in: 

• Blood sugar

• Blood pressure

• Lipid profile (cholesterol and triglycerides)

It’ll take time to see the full benefit of Zepbound. Your prescriber will work with you to make sure you’re getting the most out of your Zepbound dose while minimizing any side effects.

What should you do if Zepbound isn’t working?

Not everyone responds the same way to Zepbound, and you may not see results as soon as you’d like. If it seems like Zepbound isn’t working for you, here are some things you can discuss with your prescriber:

• Dosing consistency: You should be taking Zepbound exactly as prescribed. If not, discuss ways to stay on schedule with your dosing. 

• Staying the course: You may not need to make any changes. It may be too early to see results. 

• Dose adjustments: If it has been several months and you still aren’t seeing results, you may need a higher dose or other adjustments to your treatment plan.

• Managing medical issues: Sometimes, other health conditions like Type 2 diabetes or thyroid conditions may be interfering with weight loss.

• Reviewing medications: Other medications you take could be interfering with weight loss. 

• Pushing through the plateau: You may have hit a temporary weight-loss plateau.

• Maximizing your lifestyle: Reviewing and making adjustments to your eating and exercise plans may help you jump-start your weight loss. 

How quickly does Zepbound affect your appetite?

You may begin to notice appetite effects within the first weeks of taking Zepbound. This is typically one of the first effects of the Zepbound starting dose before your first dose increase. But keep in mind that everyone has a different experience when starting a new medication. You may notice appetite effects sooner — or not until you’ve had a dose increase.

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Written by:

Frank Schwalbe, MD

Frank Schwalbe, MD, is an assistant professor of anesthesiology at the Yale School of Medicine. He has practiced anesthesiology for 30 years.

Edited by:

Karla Robinson, MD

Karla Robinson, MD, is a medical editor for GoodRx. She is a licensed, board-certified family physician with almost 20 years of experience in health through varied clinical, administrative, and educational roles.

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