Introduction
For those suffering from type 2 diabetes or obesity, life will never be the same ever since Novo Nordisk invented semaglutide. With its efficacy, people are turning to semaglutide to help lower blood sugar levels and lose weight. Tirzepatide is a new medication that also treats type 2 diabetes. With their similar health benefits, one might wonder, ‘Is tirzepatide better than semaglutide?’
In this article, we take a closer look at semaglutide and tirzepatide. How do they work? How did their manufacturers develop them? What studies support their efficacy? And more importantly, could one be more effective than the other? Read on as we address these questions and more.
What is semaglutide?
Before we dive into a comparative review of semaglutide and tirzepatide, it’s important that we first uncover their attributes.
How semaglutide works
What is semaglutide? It belongs to a class of drugs called glucagon-like peptide-1 receptor agonists, or GLP-1 Ras. Whenever we finish eating and blood sugar levels are high, a hormone, GLP-1, triggers insulin release.
Insulin is another hormone that helps reduce glucose in the blood. GLP-1 receptor agonists like semaglutide act as GLP-1 doppelgangers, mimicking how GLP-1 prompts insulin release.
Another effect of taking semaglutide is that it delays digestion or gastric emptying, making a person feel fuller for longer. As a result, that person doesn’t feel like eating as much and loses weight.
Semaglutide is the active ingredient that brands Ozempic and Wegovys share, . Although doctors prescribe Ozempic off-label for weight management, only Wegovy has FDA approval to treat obesity.
Common and serious side effects
Regardless if you use Ozempic or Wegovy for weight management, you will still face the potential side effects.
Here are the common and serious side effects of injectable semaglutide: nausea, vomiting, diarrhea, constipation, heartburn, or abdominal pain. Healthcare providers may start you on small doses and work your way up to bigger doses to help manage symptoms.
You administer both Ozempic and Wegovy subcutaneously or under the skin.
Serious side effects
Semaglutide’s more serious side effects include allergic reactions, hypoglycemia, pancreatitis, kidney problems, and thyroid C-cell tumors. Note that these are rare.
Efficacy
Many studies have proven semaglutide’s efficacy in regulating blood sugar levels and promoting weight loss. Apart from these benefits, the drug may also play a positive role in improving cardiovascular health.
On obesity
A study looked at the efficacy of semaglutide in treating people who were overweight. 40 percent of participants—on once-weekly semaglutide—lost at least 15 percent of their body weight over 68 weeks. Those in the placebo group, meanwhile, lost significantly less weight.
On type 2 diabetes
Another study investigated the effectiveness and safety of semaglutide in treating type 2 diabetes. Some of the participants took semaglutide, while others took other diabetes medications. The results showed that semaglutide was able to reduce blood sugar levels more successfully than other diabetes drugs.
On cardiovascular problems
Clinical studies show that apart from treating type 2 diabetes, Ozempic also helps reduce the risk of developing cardiovascular issues.
Wegovy, meanwhile, appears to help reduce markers of heart disease, from high cholesterol, and high blood sugar levels, to hypertension.
What is tirzepatide?
Now that we’ve defined semaglutide, let’s learn more about its rival, tirzepatide. What exactly is it and how does it work?
Similar to semaglutide, tirzepatide is also a GLP-1 Ra. It copies GLP-1 with its insulin-triggering action. However, unlike semaglutide, a hormone called the glucose-dependent insulinotropic polypeptide (GIP) makes up tirzepatide.
The small intestine produces GIP, which plays an important role in lipid metabolism. With its dual composition of GLP-1 Ra and GIP, it may offer an additional boost in the weight loss department.
Tirzepatide goes by the brand names Mounjaro and Zepbound, which directly compete with Ozempic and Wegovy.
Like the two semaglutide brands, Mounjaro and Zepbound both come in injectable pen formats. Mounjaro is marketed as an anti-diabetic drug, while Zepbound is a weight loss drug. Both brands are manufactured by pharmaceutical company Eli Lilly.
Is tirzepatide effective?
Several studies attest to the efficacy of tirzepatide. For instance, a study found that tirzepatide was more effective than semaglutide in reducing blood sugar levels and weight loss.
The same study showed that higher doses of tirzepatide were linked to a higher risk of vomiting. This versus low and medium doses of semaglutide.
It’s worth noting that these studies only looked at weight loss in people with type 2 diabetes. Likely, the same effects might not have been the same for those without diabetes. Also, more studies need to be conducted to conclude tirzepatide’s potential effectiveness versus that of semaglutide.
Switching between tirzepatide and semaglutide
You may need to switch from semaglutide to tirzepatide or vice-versa if you are not seeing results with just semaglutide. To determine whether semaglutide is not working, your healthcare provider will likely make you undergo certain tests. These will test your blood sugar, HbA1c levels, weight management goals, and your overall health.
Switching from one drug to the other may be beneficial. It could result in better blood sugar control, greater reduction in HbA1c levels, increased weight loss, and enhanced heart health.
Still, the effectiveness of tirzepatide may not be the same for every person, as other factors come into play. It is best to closely supervise your progress and response to switching medications with your physician.
Experts point out that there are only certain drugs that can be used in tandem with others. Patients and healthcare providers need to constantly consider what the drugs are approved for and the pathways they operate in.
“One could switch between Ozempic and Trulicity—as they have the same FDA-approved indication for type 2 diabetes—or Wegovy and Saxenda, as they have the same FDA-approved indication for weight loss,” notes Kathleen Wyne, MD, PhD, an endocrinologist and clinical professor of internal medicine at The Ohio State University Wexner Medical Center. “There is no agent comparable to Mounjaro.”
Other factors to take into consideration would be the dosage and potential side effects when switching.
Patients need to check that the doses between the two different drugs are close enough not to cause adverse effects. They would also need to be comfortable switching to new administration routes, such as switching to taking the drugs subcutaneously versus orally. Generally, patients must watch what they eat and stay hydrated when switching medications or going up a higher dose.
Taking both semaglutide and tirzepatide
When taken together, semaglutide and tirzepatide could potentially lead to bigger improvements in controlling blood sugar levels and weight management. Taking the two could result in more effective reductions in blood sugar levels, weight loss, controlled appetite, and food cravings. In addition, it could contribute to improved insulin sensitivity, as well as improved overall metabolic health.
However, patients should always consult their doctor before modifying their treatment plan.
Cost and supply issues
It’s important to consider factors such as cost and availability. Tirzepatide is more expensive than semaglutide and is more effective in controlling blood sugar levels and promoting weight loss.
According to a November 2024 report, semaglutide brands had the following pharmacy retail prices for one month’s supply:
- Ozempic: $830-870 (list price at $968.52)*
- Wegovy: $1,237-$1,340 (list price at $1,349.02)*
- Rybelsus: $848-$917 (list price at $968.52)*
Meanwhile, semaglutide’s rival brands cost around $935 to $1,070 a month without insurance.
Ongoing shortage problem
Ongoing supply issues, as well, continue to plague semaglutide manufacturer Novo Nordisk and its competitors. Towards the latter part of 2023, there was a major shortage in Wegovy and Ozempic amid the clamor for the drugs. The shortage problem will likely persist for several more years.
Novo Nordisk admitted a “short-term stock-out” of Wegovy in the US through December due to demand surpassing supply capacities.
***Note: Prices are subject to change.
Conclusion
Semaglutide and tirzepatide are two drugs that are changing the lives of people suffering from type 2 diabetes and obesity. Amid the massive popularity of semaglutide brands Ozempic and Wegovy comes the rise of tirzepatide, sold as Mounjaro and Zepbound.
Although tirzepatide shares similarities with semaglutide, such as also being a GLP-1 receptor agonist, it functions slightly differently. Tirzepatide is also made up of the hormone glucose-dependent insulinotropic polypeptide (GIP). With its dual composition of GLP-1 Ra and GIP, tirzepatide may offer an additional boost in the weight loss department.
While semaglutide and tirzepatide function similarly, a study revealed that tirzepatide may be more effective than semaglutide for weight loss. However, the higher the dose of tirzepatide, the higher the risk of gastrointestinal side effects. These include constipation, diarrhea, upset stomach, or abdominal pain.
Due to concerns like cost and availability, some patients may opt to switch between medications such as semaglutide and tirzepatide. Despite its greater efficacy, tirzepatide is more expensive than semaglutide, though. An ongoing supply shortage has also been plaguing drug manufacturers due to the demand for weight loss drugs. It will likely take a few more years to be resolved.
Patients must consider drugs’ administration, dosage, and their lifestyle choices as these may affect medicines’ efficacy when taken together. It is also best to switch between type 2 diabetes or weight loss drugs. This is applicable so long as they are approved and intended for the same use.
As with any medicine use, it should be under the guidance of your healthcare provider.
Image by Freepik
