Image credit: New You Wellness Center
Have you heard of Zepbound™, the latest FDA-approved weight loss medication? Zepbound™ is essentially the FDA-approved version of tirzepatide for weight loss. If you’re not familiar with it, tirzepatide is the active ingredient in Mounjaro, a diabetes medication that has been used off-label for weight loss.
If you’re feeling confused with all these weight loss medications or are waiting to gain access to one of them, you are not alone. With so many new meds coming out every few months with different ingredients, results, and price points, it’s really easy to get overwhelmed. If you’re curious if these medications are for you or what questions to ask, I got you.
This article will review what we know so far about the latest medication, Zepbound™ (generic name tirzepatide) which to date has produced the largest weight loss results of any medication.
What is tirzepatide?
Tirzepatide is traditionally a medication used to treat type 2 diabetes and is the active ingredient found in the diabetes drug Mounjaro. Since many started to use tirzepatide for weight loss, it has gained popularity for off-label use by many people.
Off-label use means the medication is being used for reasons other than what it is approved for by the FDA. So until now, tirzepatide has been used for weight loss under the diabetes drug name Mounjaro because weight loss often occurs as a side effect. However, it wasn’t FDA-approved for weight loss, and so doctors prescribing it for that purpose were technically doing so illegally.
The good news is as of November 2023, tirzepatide is now approved for weight loss under the drug name Zepbound™. It is not yet on the market but is expected to be available by the end of 2023.
Zepbound™ is made by a company called Elli Lilly, a competitor of Novo Nordisk. Ozempic and Wegovy (which contain semaglutide as the primary ingredient) are made by Novo Nordisk.
When considering all the current weight loss meds out there, Zepbound™ is most similar to Wegovy, but produces greater weight loss.
How do you qualify for tirzepatide?
To be eligible for a tirzepatide prescription, you must have a BMI of 27 with at least one weight-related condition or a BMI of 30 or above.
How does tirzepatide work?
Tirzepatide injections are given once a week for weight loss in 6 incremental doses – 2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, and 15 mg.
Zepbound™, like its diabetes counterpart Mounjaro, is known as a “double-agonist” drug that activates two hormone pathways in the body to help you lose weight. This is in contrast to “single-agonist” drugs like Ozempic and Wegovy, which only involve one single pathway.
It is possible that this characteristic is responsible for much of the higher weight loss results seen with Zepbound™ on average when compared to Ozempic and Wegovy.
Two key hormones
The two hormones that Zepbound™ targets are GLP-1 (glucagon-like peptide-1) and GIP (gastric inhibitory polypeptide).
GLP-1 helps slow digestion, making you feel more full, and reduces the release of glucose (i.e. sugar) into the bloodstream. This can help reduce blood sugar, which is helpful for those with diabetes but can also help regulate energy levels and appetite.
GIP stimulates insulin secretion after a meal and also slows digestion. Its action helps signal your body that you’re full and also can reduce blood sugar levels.
Tirzepatide, or Zepbound™, helps to mimic the effects of these two hormones to stimulate insulin secretion and delay stomach emptying after a meal. The result for many people is increased fullness with less food, making it easier to eat less.
Tirzepatide for weight loss – what the data shows
The largest study on Tirzepatide involved over 2500 adults in 2022. Participants received either a once-weekly Tirzepatide injection or a placebo for 72 weeks. All participants also followed a calorie deficit of 500 calories a day, were advised by a health professional to make healthful meals, and engaged in at least 150 minutes of exercise per week.
Doses started at 2.5 mg and were increased by 2.5 mg every 4 weeks. This progressed this way until the highest dose of 15 mg per week was reached.
Results: Those taking tirzepatide lost an average of 27% of their total body weight, or about 64 pounds. By comparison, those who got the placebo lost about 4% of their body weight, or about 9 pounds.
This amount of weight loss is comparable to weight loss from bariatric surgery in the same time frame.
Zepbound™ is not yet on the market, but it is predicted to cost over $1,000 monthly, similar to other GLP-1 and GIP medications. Some may be covered by insurance, depending on your insurance plan, and hopefully, in time, these medications will become more universally covered.
The most common Tirzepatide side effects are gastrointestinal and include nausea, diarrhea, bloat, and abdominal pain. These side effects typically worsen with increased dosages but have also been seen to level off at times before the highest dose.
Muscle loss is also common and can be significant if the proper lifestyle measures are not taken. Eating enough protein and performing weight-bearing exercises 2-3 times a week are the two most effective ways to reduce muscle loss. When we work together, I provide specific guidance on how much protein you need each day and create a plan on how and when to get it in to meet your daily needs.
More rare but severe side effects are also possible, which include:
- Increased heart rate
- Acute kidney injury (usually due to dehydration if diarrhea is occurring)
- Allergic reactions at the injection site
- Liver or gallbladder damage
- Vision issues
Black box warning: There is a boxed warning from animal studies that have shown tripeptide has the potential to increase the risk of medullary thyroid carcinoma. For this reason, if you have a personal or family history of this type of thyroid cancer or another cancer called multiple endocrine neoplasia syndrome type-2 (MEN 2), it is recommended not to take tirzepatide.
Reducing the Risk of Side Effects
You can reduce the likelihood of milder side effects in a few ways. First, limit high-fat or sugary foods such as fried foods, red meat, and sweets. High-fat foods take a long time to digest and can be heavy on the stomach, worsening gastrointestinal side effects from these medications that already slow down your digestion.
In addition, sweets are high in sugar which can raise your blood sugar and lead to blood sugar crashes and hypoglycemia, especially when many of these weight loss medications lower your blood sugar to begin with.
Paying attention to when you’re getting full, eating slowly, and consuming small frequent meals can also help.
Who Should Not Take Tirzepatide?
Those who have a personal or family history of thyroid cancer, are pregnant or breastfeeding and have a history of an eating disorder should not take tripeptide.
Tirzepatide vs Ozempic vs Wegovy
Compared to Ozempic and Wegovy which contain semaglutide as their primary ingredient, tirzepatide for weight loss appears to be more effective. More research is still needed into the overall safety and long-term effects of staying on Tirzeptade. It is likely that these medications need to be taken long-term to maintain weight loss.
If you do need to come off of them due to side effects or other reasons, working closely with your doctor and a registered dietitian specializing in weight loss is essential. This can reduce the likelihood of weight regain and help you navigate increased cravings, hunger, or challenges you face when coming off of them.
Bottom Line on These Medications
Weight loss medications like Zepbound™ have some serious potential to consider in terms of assisting with the weight loss process. However, there is still a lot that we don’t know in terms of their overall safety and effectiveness long-term and what happens once you come off of them.
Can you take them indefinitely? Will you regain the weight back when you come off? These are still unanswered questions that the scientific community continues to investigate.
Research thus far shows weight regain is common after discontinuing these medications, and many people regain up to ⅓ of their weight. Working closely with a registered dietitian while taking these medications is essential for continued support and guidance in following the proper diet and lifestyle habits to promote weight loss maintenance.
This can help increase your chances of permanent weight loss, which, of course, is the ultimate goal.
Get Support on Your Weight Loss Journey
If you need more support navigating your diet, lifestyle, and potentially weight loss medications, contact me to schedule a free nutrition strategy call. We’ll talk through your goals, what you’ve tried, and see if my sustainable weight loss program is a good fit for y