Zepbound looks set to be one of the hottest weight loss drugs of 2024.
If you have never heard of Zepbound, you may be familiar with its sister product. It's called Mounjaro.
Actually, using the word sister doesn't cut it because Zepbound is Mounjaro's identical twin. Both medications provide the same drug. It's called Tirzepatide. The name is the only difference. Zepbound and Mounjaro don't just provide the same drug; they provide it in identical amounts.
When Is Zepbound Available in Pharmacies
Consumers will be able to order Zepbound over the counter in pharmacies in the first quarter of 2024—you will need a prescription from your doctor.
Zepbound vs. Mounjaro: What You Need to Know
Tirzepatide was originally developed to control blood sugar levels in type 2 diabetics. The FDA approved its use on May 13, 2022 [1], and the manufacturer, Eli Lilly and Company, has been distributing it under the Mounjaro brand name ever since.
Tirzepatide is a GLP-1 receptor agonist that's delivered to the body once weekly via subdermal injections.
Drugs of this type are known to present a number of side effects. One of the most common issues among users is loss of appetite, so it's not surprising that Moujaro quickly became a popular off-label treatment for weight loss.
Nor is it surprising that Lilly fast-tracked the evaluation of its rebranded version of Terzapatide for weight loss. The FDA approved it on November 8, 2023. [2]
At its most basic, Tirzepatide is a synthetic form of GLP-1 (glucagon-like peptide-1). GLP-1 is a gut hormone that encourages the release of the pancreas hormones (insulin and glucagon) that regulate blood sugar levels.
It's this ability that furnishes GLP-1 receptor agonists with their value as anti-diabetic treatments.
However, GLP-1 also acts on the brain in ways that reduce hunger. It further suppresses hunger by delaying gastric emptying.
Drugs that mimic its abilities can do these things as well, and there are several options available. One of the most popular ones is Semaglutide, which is available under the Ozempic and Wegovy brand names.
Ozempic has FDA approval for treating type 2 diabetes, and Wegovy is approved for weight loss. However, in this case, the twin medications are not truly identical because there are some differences between the doses.
Zepbound vs. Wegovy
Research suggests people using Zepbound may lose more weight than those who are using Wegovy.
But perhaps that's not so surprising because Zepbound has an additional ability that Wegovy does not. It also mimics the actions of a satiety hormone called GIP (glucose-dependent insulinotropic polypeptide).
What is surprising is the price difference. Despite appearing to have superior abilities, Zepbound is considerably cheaper than Wegovy.
A 4-week supply of Wegovy has a list price of $1,349.02. The list price for a 4-week supply of Zepbound is $1,059.57 for a 4-week supply.
Evaluating Zepbound's Ability to Support Weight Loss
The FDA approved Zepbound's use for weight management based on the way the medication was performed in two clinical trials.
In both cases, the evaluation period was 72 weeks, and all those involved had to make appropriate efforts with diet and exercise.
The smaller of the two studies was conducted on overweight and obese adults with type 2 diabetes. On average, the participants given the medication showed 12% reductions in body weight.
The larger study was conducted on non-diabetic adults who were overweight or obese. In this case, the participants taking the medication reduced their body weight by 18%. [2]
During the clinical trials that earned Wegovy its FDA approval, the most notable weight reduction was 12.4% after 68 weeks. [3]
Zepbound Administration and Dosage
Zepbound is distributed in injector pens that contain one dose of Terzepatide in varying amounts. There are six dosage options available. The lowest dose pen provides 2.5 mg of Tirzepatide per shot. This is the pen doctors prescribe for the first month of treatment.
The pen for the second month of treatment provides 5 mg of Tirzepatide. Each month, the pen/dose increases in 2.5 mg increments until the maximum dose (15 mg of Tirzepatide) is reached.
The needle is hidden inside the device. There is no need to see it. All you do is press the end of the pen against the skin and maintain sufficient pressure. The hidden needle does all of the work.
The recommended injection sites are the upper thighs, the upper arms, and the abdomen.
As with all prescription weight management drugs, Zepbound is intended to be used alongside diet and exercise.
Zepbound Eligibility and Suitability Considerations
Zepbound is not suitable for people who have certain medical conditions, such as pancreas issues or kidney problems.
It may also be unsuitable for people who are using certain types of medications. Women who are using birth control pills as a primary form of contraception also need to be aware that Zepbound may stop their pills from working.
Women who are pregnant or trying to become so need to know that Zepbound may harm their unborn baby.
In addition to being unsuitable for some people, Zepbound may also be unavailable to them because the FDA only permits doctors to prescribe it to adults who are obese (BMI of 30 kg/m2 or greater).
People who are overweight but not obese (BMI of 27 kg/m to 29.9 kg/m2) may be eligible as well, but only if they have at least one weight-related comorbidity, such as obstructive sleep apnea.
Zepbound Side Effects Risks
The most commonly reported side effects during clinical trials were gastrointestinal reactions such as constipation, nausea, and/or vomiting.
Side effects such as these are common to all the weight loss injections that mimic the abilities of GLP-1.
Zepbound also appears to have the potential to cause hair loss.
Animal testing suggests GLP-1 receptor agonists may have the potential to cause thyroid cancers. Because of this, the FDA insists they be distributed with appropriate warnings.
Other potential side effects of a more dangerous nature include kidney damage, swollen pancreas (pancreatitis), and gallbladder issues.
Zepbound may also cause psychiatric side effects in some people, such as depression or thoughts of suicide.
How Zepbound Compares to the Alternatives
As we have already discussed, Zepbound's closest competitor is Wegovy. It's cheaper than Wegovy and appears to have greater potential. The risk of side effects is about the same.
In fact, as far as the risks and side effects go, Zepbound is probably no better or worse than any of the other popular weight loss injections. It does beat a few of them on ease of use, though. Certain options, such as Victoza (Liraglutide), require daily injections.
Weekly injections are more desirable for several reasons. For one thing, they are less likely to cause skin irritation. For another, they are more convenient. With careful planning, most people should be able to pick and stick to an injection day when they know they will not have to be at work.
Of course, Zepbound will be a particularly poor choice for anyone who has a strong aversion to needles. In this case, the needle is hidden, but just the thought of needles entering their skin may be enough to put some people off.
At the other end of the scale, people who find it difficult to swallow pills may find Zepbound an attractive alternative.
However, as with most of the other weight loss medications that have FDA approval, Zepbound is somewhat limited in its abilities. All it does is suppress appetite. Most Zepbound alternatives are far more versatile. In addition to controlling hunger, they increase energy, boost metabolism, and/or provide help in additional areas.
Zepbound appears to trump the abilities of many alternative pharmaceutical options but is somewhat lacking when compared to many of the best natural alternatives.
Research Sources
1) FDA Approves Novel, Dual-Targeted Treatment for Type 2 Diabetes: https://www.fda.gov/news-events/press-announcements/fda-approves-novel-dual-targeted-treatment-type-2-diabetes
2) FDA Approves New Medication for Chronic Weight Management: https://www.fda.gov/news-events/press-announcements/fda-approves-new-medication-chronic-weight-management
3) FDA Approves New Drug Treatment for Chronic Weight Management, First Since 2014: https://www.fda.gov/news-events/press-announcements/fda-approves-new-drug-treatment-chronic-weight-management-first-2014
