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How fast does semaglutide work? 

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How fast does semaglutide work? 


If you’re reading this article, I can reasonably assume you are looking to lose weight. Perhaps you want to lose weight by a deadline: wedding, class or family reunion, surgical deadline, or other personal reasons. You found this article by wondering – how fast does semaglutide work?

To answer this question, I believe it’s valuable to have a baseline understanding of the medication and how it works first. Don’t worry; this won’t take too long.

What is semaglutide?

Semaglutide is a newly FDA-approved weight loss medication sold under the brand name Wegovy. It is a once-weekly injectable medication that is given as a minimal dose to start and gradually increased until a therapeutic dose is reached.

Semaglutide belongs to a class of medications called GLP-1. Patients with type II diabetes initially used this class of drugs when metformin, the medicine typically used to manage diabetes, failed. It has been a very effective medication for lowering blood sugar for many years, with the added benefit of weight loss.1

In response to the weight loss seen in patients with type II diabetes, Novo Nordisk sent semaglutide into FDA trials for approval as a weight loss medication. In 2021, semaglutide was approved, and Wegovy was available to patients as a once-weekly injectable to treat obesity.2

How does it work?

Though the exact way that semaglutide causes weight loss is unclear, it has some specific functions that are believed to be responsible for its weight loss effects.
A not-so-obvious but very beneficial effect of semaglutide includes its impact on the brain.

Semaglutide acts on the hypothalamus, a part of the brain that you could think of similar to a thermostat that controls more than just the body temperature. 
The hypothalamus also regulates our mood, blood pressure, sleep, and even sex drive. But an essential function related to weight loss is the sensation of hunger and fullness controlled by the hypothalamus.1

Semaglutide alters the food-reward system and prolongs our sense of fullness. Patients taking this medication at our practice routinely tell us they no longer crave their favorite unhealthy foods. They have an easier time opting for lower fat and healthier options.4

Finally, semaglutide slows down the motility of the gastrointestinal tract. Put more simply, semaglutide keeps the food in your stomach for longer than usual, keeping you full longer.

Is it safe?

With all the changes semaglutide makes to the body, it would be natural to wonder – is semaglutide safe?
While no medication is without risks and side effects, semaglutide is relatively safe for most people. Semaglutide can be used in people with most heart, kidney, liver, and endocrine conditions.

Before obtaining a prescription, your provider needs to have a thorough conversation about your medical history to be confident that you are safe to begin taking semaglutide.

How fast does semaglutide work?

Now that we have established a basic understanding of semaglutide, we can discuss how fast it works to cause weight loss.  

The answer to this is multifactorial and requires a bit of explanation. The short answer is that many of our patients lose weight in the first week of taking semaglutide. The first dose is small (0.25 mg). It is primarily used to gently introduce the medication to the body without risking developing severe side effects.

Here at Rivas Medical Weight Loss, we understand that it is possible to “out-eat” any weight loss medication. In other words, you may see little to no weight loss in the early weeks without making lifestyle changes.  

How fast can you increase the dose?

If you were to obtain branded Wegovy, you would receive one month’s worth of injections at a time and increase no faster than one month at a time. In other words, you would receive one month (4 injections) of 0.25 mg, one month (4 injections) of 0.5 mg, and so forth to 1.0 mg, 1.7 mg, and finally 2.4 mg, assuming your side effects are minimal. 5

In our practice, we weigh three primary factors when deciding how to increase the dose for our patients.

We will discuss whether you experienced side effects that week and, if so, whether they were mild or severe. We will discuss how well semaglutide managed your hunger that week. In lower doses, hunger suppression may not noticeably last for a whole week, even though the medication may still work in other ways. Finally, we assess how much weight you lost that week.  

How fast we increase the dose for our patients is individualized and tailored to the needs of each patient. We can accomplish this because we do not use branded Wegovy. Instead, we have our semaglutide compounded by a pharmacy and sent directly to our clinics, where we dispense it to the patient at each visit.

Therefore, no two patients have the same rate of increase. The individualized approach allows us to maximize the benefits of the medication while keeping side effects to a minimum.

How long do I need to take semaglutide to see results?

Suppose you adopt the healthy lifestyle changes we recommend at your consultation. In that case, you could see results as early as the first week. Healthy sustainable weight loss is 0.5 – 2.0 pounds a week. 

We have patients who routinely surpass this rate of weight loss. While the medication certainly plays a role, we cannot ignore other factors. These factors may include high BMI at the start of the therapy, adherence to nutritional guidelines, presence or absence of exercise and the type of exercise used, and more.

It is essential to keep a realistic perspective about the rate of weight loss that you can achieve.

Our goal at Rivas Medical Weight Loss is to provide our patients with the tools and information to achieve a reduced weight and maintain the loss long term.

The rate at which you reach your goal will most likely not be the same as someone else. “Comparison is the thief of joy.” This quote is attributed to Teddy Roosevelt, sage wisdom that we may all do well to adopt into a weight loss mindset.

How much weight can I lose with semaglutide? 

The average weight loss achieved in the STEP 1 study of semaglutide for weight loss was 14.9% of the initial body weight over 68 weeks. Individual loss varies and depends on how seriously a person commits his, her, or their self to investigating their personal reasons for eating outside of feeling hungry. Likewise, adjusting food intake to appropriate portions and choosing healthier options regularly.1 

In our practice, it is not unusual to see a patient lose roughly 20% of their starting body weight during treatment. This amount of weight loss is a testament to the commitment made by those patients to improve their relationship with food with sustained positive changes over time.

Semaglutide, or any other weight loss medication, is a tool to assist in weight loss while the patient makes other lifestyle changes. No magic pill (or injection) will change your relationship with food. The patients who lose the most make healthy choices most of the time.

Do I need to take semaglutide for the rest of my life? 

The STEP 1 study lasted for 68 weeks. Unfortunately, we have no follow-up information from those patients to assess whether study participants maintained their weight loss after stopping the medication. 

However, nutrition is an essential factor in weight loss. Medication is helpful but may not be necessary forever if you can adopt positive lifestyle changes and continue them after you stop taking semaglutide.

It would be beneficial to have a personal discussion with a medical provider for people with other medical conditions that affect weight gain. You can discuss your concerns and develop an individual plan for how long you want to use semaglutide to help manage weight.

Ready to Start?  

Do you want to see if semaglutide is right for your weight loss journey? Call your nearest Rivas Medical Weight loss location to book a consultation and let us help you reach your goals. Our caring and compassionate providers are happy to discuss your unique situation and help you find the best medication for you.

Kristi Perry



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Ben Flores
Ben Flores
Tanya Colonette
Tanya Colonette
Dynamic Balboa
Dynamic Balboa
Dr. Mahrukh at Rivas is the best! I've lost 17lbs so far. She's informative and professional. I've been coming for 2 months and my results are amazing.
Thanks to Rivas, I have successfully lost 50 lbs! Maybe I could’ve done this with the other locations, but this particular location has the friendliest staff. They are professional, non-judgmental, and get their patients in and out so quickly! Definitely recommend!
Lorraine Mendez
Lorraine Mendez
Janine Sasser
Janine Sasser
Rivas is a wonderful place! I enjoy the staff there, all of them are very nice & very helpful. I'm glad I chose to go there for Weight Loss. Sophia is my PA I see, she's great 👍🏼
Luis Herrera
Luis Herrera
Since I was referred to Rivas Medical Weight Loss by my Manager who is a patient as well, my life has been changing a lot.All staff is so friendly and make me feel so welcome every time I come here.*Rockville Office:I always feel comfortable with Kristin because she is friendly and professional, she always is direct and sure of herself what she is going to say. Thank you 🙏 for all the advises I get every visit and thank you all the clinic staff.Thank you Rivas Medical Weight Loss- Luis Herrera-
Duane Pickett
Duane Pickett
David Mitchell
David Mitchell
Competent, connecting, & caring.
Roseann Brooks
Roseann Brooks
Super super friendly staff. Doctors car about the patients not the money. 100% a place to go.
Tracey T.
Tracey T.
Very professional. Nice having medical staff to guide you through the process
Anna Gruber
Anna Gruber
The staff are all very kind and inviting, and willing to support you in any situation.
Lady Prada
Lady Prada
4 Month Update:The staff continues to be amazing, knowledgeable and caring. They have been very supportive my entire journey. Highly recommend.Update: The entire staff is amazing. I added a vitamin shot today and boy the energy is amazing!!! Highly recommend! 10 stars!!!I highly recommend Rivas Weight Loss Center in Rockville. The staff is super helpful, knowledgeable and kind. I have never felt judged or uncomfortable there. The staff goes out of their way to make sure everything is great and answer any questions or concerns. I am so thrilled that I have found them and I have referred family and friends to them as well!