Switching to Zepbound: What you need to know

Zepbound®, the most recent FDA-approved medication to treat weight loss, has attracted a lot of interest from patients seeking an effective weight loss solution. Clinical trials of Zepbound have demonstrated the greatest weight loss seen with any FDA-approved medication to date. If you are currently taking a weight loss medication, you may be wondering if you should make the switch to Zepbound from your current medication. In this blog, we will discuss ways to determine whether Zepbound is right for you and what you need to know if you do make the switch.  

Evaluating your current weight loss strategy

If you are considering switching to Zepbound, it is important that you first ask yourself the following questions about the current medication you are taking:

• Am I experiencing side effects from my current medication? If the side effects are not getting any better as time has gone on or are getting worse, then maybe it’s time to consider a change. It’s also important to consider that you may also experience side effects with Zepbound.
• How long have I been taking this medication? Guidelines recommend a trial of at least 3 months of a weight loss medication, as long as there are no major side effects, with a goal of at least 5% total body weight loss to help determine whether the medication is effective.
• Have I been using my medication correctly? Weight loss medications must be used in combination with lifestyle changes. These include following a low calorie eating pattern  and aiming for at least 150 minutes of moderate intensity physical activity weekly. If you have not been doing so, what are the barriers? If you are very active but your appetite is preventing you from reducing your calorie intake, then maybe a medication change is warranted. If, however, you have not fully committed yourself to the lifestyle changes then you should ask: Am I ready for weight loss? 
• Is my current medication affordable and available when I need it? Some of the newer weight loss medications can cost over $1,000 per month if not covered by insurance.  While it may be a cost you can afford in the short term, it’s important to know that weight loss medications are intended for long-term use because stopping the medication typically leads to weight regain. Shortages have also been a major challenge among the injectable weight loss medications. Given the tremendous demand for these medications and shortages that have occurred with Saxenda®, Wegovy®, Ozempic® and Mounjaro®, it would not be unreasonable to anticipate similar issues affecting the supply of Zepbound. You can check current supply status on the FDA Drug Shortage list.

Zepbound: A promising alternative

Zepbound was approved by the FDA for weight loss treatment in adults living with obesity (BMI 30+) or overweight (BMI 27+) with one or more weight related medical conditions in November 2023. The SURMOUNT-1 trial demonstrated an average of 22.5% body weight loss after taking the highest dose of Zepbound for 1 year, more than what had been observed in studies of a similar medication Wegovy.  Zepbound contains tirzepatide, the same active ingredient as Mounjaro®, a medication FDA-approved for the treatment of type 2 diabetes. 

How Zepbound works

Zepbound works for weight loss by mimicking both glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) which are two naturally occurring hormones in the body. GLP-1 acts on the brain to decrease appetite and cravings and also slows stomach emptying, making you feel full sooner and for a longer period of time.  GIP affects lipid (fat) and glucose metabolism, improves insulin sensitivity, and augments the effects of GLP-1 to further support weight loss. 

Why switch from a different weight loss medication to Zepbound?

You may consider switching to Zepbound for a number of reasons including side effects of your current medication, poor availability due to shortages, weight loss plateau, or minimal weight loss, or change in insurance coverage. It is important that you consult with your healthcare provider to discuss if Zepbound would be an appropriate medication for you.

Switching from Wegovy to Zepbound

Wegovy is a weight loss medication that was FDA-approved in June 2021. It is a once-weekly injectable medication that mimics GLP-1 only. If you are currently taking Wegovy and implementing lifestyle changes without expected weight loss results, you may consider switching to Zepbound. Because Zepbound works differently in the body to stimulate weight loss by targeting both the GLP-1 and GIP receptors, rather than just GLP-1, it may prove to be more effective for some patients. You should have a conversation with your healthcare provider to be sure to understand the key differences between Zepbound vs. Wegovy and determine if you should make the switch.

Switching from Mounjaro to Zepbound

What is the difference between Mounjaro vs Zepbound? Both Mounjaro and Zepbound contain the same active ingredient, tirzepatide.  The main difference is that Mounjaro is an FDA-approved medication for the treatment of type 2 diabetes while Zepbound is FDA-approved for weight loss. Prior to the FDA-approval of Zepbound for weight loss, some patients without type 2 diabetes were prescribed Mounjaro for the treatment of obesity because studies demonstrated significant weight loss in people taking tirzepatide. Prescribing Mounjaro to patients without type 2 diabetes is considered off-label prescribing. Note that off-label prescribing is a legal and common practice in the US. If you are currently taking Mounjaro for weight loss, the decision to switch to Zepbound is usually based on insurance coverage and cost as both medications have the same active ingredient and the dosages are the same.

Making the switch to Zepbound: What to expect

Making a smooth transition to Zepbound is possible by working closely with an experienced medical clinician and ensuring that you are well informed about the medication before getting started. 

The transition process: How do you safely switch from your current medication to Zepbound?

Making any medication change should be done in consultation with a medical clinician. This is important to ensure your safety,that the switch is medically appropriate, and that you are informed about the risks and benefits of making a change. Your healthcare provider should provide personalized guidance on dosage and administration of Zepbound, as well as monitor your response to the medication and address any side effects that occur. Regular check-ins with your medical clinician are the best way to ensure that Zepbound is a safe and effective medication for you. 

Recommendations on what dose of Zepbound to start with should be made by your medical clinician. If you are taking a GLP-1 medication such as Wegovy or Saxenda and switching to Zepbound you should not continue to take your GLP-1 medication after starting Zepbound

Initial side effects: What should you be prepared for when starting Zepbound?

The side effects of Zepbound are very similar to those of GLP-1 receptor agonists like Wegovy and Saxenda, but they may be less intense as a result of the dual GLP-1/GIP agonism. Common side effects of Zepbound can include:

• Nausea
• Vomiting
• Diarrhea 
• Constipation
• Heartburn 
• Abdominal pain
• Fatigue

Gallbladder disease is another potential side effect, and other rare side effects have been reported. It is important to note that Zepbound side effects will vary from person to person and can be affected by many factors including medical history, medications, and lifestyle. You should discuss any concerning side effects with your prescribing healthcare provider.

Setting realistic expectations: What results can you anticipate with Zepbound?

Individual responses to taking Zepbound for weight loss will vary. Zepbound is intended to be used in combination with a healthy, reduced-calorie eating pattern and increased physical activity along with behavior changes to support a healthy lifestyle long-term.

You can get an idea of the average amount of weight loss people experience from the clinical trials of this medication. The SURMOUNT-1 trial demonstrated an average of 22.5% body weight loss for patients taking the highest dose of Zepbound (15 mg) at 1 year. Another study, SURMOUNT-3, looked at patients who lost at least 5% of their body weight after 3 months with lifestyle changes and then started Zepbound. At 72 weeks on Zepbound, patients lost 26.6% of their body weight. 

Typically, when you start a weight loss medication, it is expected that you should lose at least 5% of your starting body weight after 3 months on the medication. That means if you weigh 200 lbs, after 3 months you should have lost 10lb, if not more. If you are struggling to lose weight while taking Zepbound or are losing less than would be expected, speak with your medical clinician to better understand what may be slowing your progress or if a medication change should be made.

Getting your medication: What changes to insurance coverage and cost should you expect?

The cost of switching to Zepbound will ultimately depend on your insurance plan. If Zepbound is not a covered benefit (not on your insurance formulary) or weight loss (anti-obesity) medications are considered a plan exclusion, then insurance will not pay for the medication. Note that just because you have coverage of one weight loss medication or meet the FDA-prescribing criteria for taking Zepbound, it does not mean Zepbound will be covered by your insurance.

The best way to determine whether Zepbound is covered by your insurance is to refer to your plan’s drug formulary, or to call your insurance company directly to understand your coverage options. If it turns out Zepbound is covered, your insurance may require you to try other medications first before they will cover Zepbound. Additionally, coverage of a medication does not necessarily mean zero cost. There may still be copayments or a deductible you need to first meet. 

Finding the right weight loss solution for you

Making the switch to Zepbound may not be right for everyone, and it is best to consult with an experienced medical clinician to determine whether this medication is the right choice for you. At Form Health, you work closely with your doctor who is board certified in obesity medicine which means your doctor has specialized training and experience in treating obesity. Additionally, you meet regularly with your Registered Dietitian who is an expert in weight management to support you with the lifestyle changes crucial to long-term success. Our team works to support you throughout your weight loss journey, including with making the switch from one medication to another. 

Find out if you are eligible by taking our quiz or send a message to get in touch with us directly at info@formhealth.co.

Zepbound® and Mounjaro® and their delivery device bases are registered trademarks owned or licensed by Eli Lilly and Company, its subsidiaries, or affiliates.

Wegovy® and Saxenda® are registered trademarks of Novo Nordisk A/S.