Tirzepatide and semaglutide are type 2 diabetes drugs often used for weight loss. Tirzepatide is less expensive and may be more effective. However, the drug is still new, and more research is needed.
Using medications for weight loss is becoming more common. Doctors sometimes prescribe newer type 2 diabetes drugs to help with weight management. This use is “off-label,” meaning that doctors prescribe the drug for a use that’s different from the one the Food and Drug Administration (FDA) has approved for.
Two drugs that doctors prescribe for weight loss are tirzepatide and semaglutide. Both drugs can help your brain feel less hungry, but there are some differences to consider with a doctor’s guidance. Research is still unclear as to which of the two medications might be a better option for weight loss.
When you eat, your digestive tract releases the hormone glucagon-like peptide-1 (GLP-1), which prompts your body to create more insulin. This hormone can also send fullness signals to your brain. Semaglutide is a GLP-1 receptor agonist that mimics the hormone, making you feel less hungry.
Semaglutide is FDA-approved to treat type 2 diabetes under the brand names Ozempic and Rybelsus. Wegovy is the only semaglutide drug that’s
Tirzepatide is a glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 receptor agonist that
Tirzepatide is sold under the brand name Mounjaro, which is also approved only to treat type 2 diabetes. However, tirzepatide may be prescribed for weight loss under the brand name Zepbound.
Note that semaglutide is available as either an oral tablet or an injection, whereas tirzepatide is available only as an injection.
Some recent studies have compared semaglutide and tirzepatide for weight loss. Research studies from
But there are some important caveats to these studies.
The doses of semaglutide and tirzepatide given to participants were not equal. Semaglutide and tirzepatide work slightly differently, so the researchers chose comparable dose levels. However, the dose of tirzepatide was higher, which may have affected the results.
Tirzepatide is currently
However,
The side effects of tirzepatide and semaglutide are similar. Moderate side effects of tirzepatide and semaglutide can include:
- constipation or diarrhea
- upset stomach, nausea, and vomiting
- headaches
- abdominal pain
- fatigue
- hypoglycemia (low blood sugar)
More severe possible side effects of tirzepatide and semaglutide include:
- vision changes
- pancreatitis
- kidney failure
- gallbladder issues
- allergic reactions
Both of these medications have boxed warnings about the risk of thyroid C-cell tumors. A boxed warning is the most serious warning from the FDA.
Tirzepatide warning
There are still questions about the side effects of tirzepatide in people without type 2 diabetes. Weight loss is a relatively new use for these medications, and they may have limitations and side effects that research has not yet identified.
Your doctor and healthcare team can give you the best guidance on these medications and any symptoms you may be experiencing when using Mounjaro in particular.
The following table compares the dosages of Wegovy and Zepbound, which are the brand-name medications approved for weight loss. Because the two drugs work differently, the dosing amounts are different.
However, your dosage may vary based on your doctor’s recommendation and on whether they choose to prescribe one of the other brand-name drugs off-label.
The doses are measured in milligrams (mg).
| Medication | Weeks 1 through 4 | Weeks 5 through 7 | Week 8 and beyond | Maintenance doses |
|---|---|---|---|---|
| Zepbound | 2.5 mg once per week | 5 mg once per week | may be increased by 2.5 mg once per week every 4 weeks, up to 15 mg | 5 mg, 10 mg, or 15 mg once per week |
| Wegovy | 0.25 mg once per week | 0.5 mg once per week | • Weeks 9 through 12: 1 mg once per week • Weeks 13 through 16: 1.7 mg once per week | 1.7 mg or 2.4 mg once per week |
How much do semaglutide and tirzepatide cost?
Your out-of-pocket cost depends on whether your insurance covers these medications. The pharmacy price of three packages of Zepbound is around $3,000, while for Wegovy, that price is about $4,000 for the same amount. Note, however, that the prices at different pharmacies can vary.
According to a 2023 study, 72 weeks of treatment with tirzepatide cost about
Can I switch from semaglutide to tirzepatide?
It’s generally considered safe to switch from semaglutide to tirzepatide. In fact, research suggests that switching from semaglutide to tirzepatide may even be beneficial for weight loss. That said, you should take these medications only under the supervision of a doctor and should consult your doctor before switching.
What are the disadvantages of tirzepatide?
Like other GLP-1 drugs, tirzepatide can cause side effects.
How fast do you lose weight on tirzepatide?
While this can vary from person to person, a 2022 study suggests that you could start seeing weight loss within weeks.
Tirzepatide and semaglutide are type 2 diabetes drugs that doctors often prescribe for weight loss. Tirzepatide may be more effective because of how it works, but current research is inconclusive. It’s too early to know for sure whether one drug is more effective than the other, especially in people without diabetes.
Several studies suggest that tirzepatide is more effective in helping people with type 2 diabetes lose weight, but the research isn’t definitive. Your doctor can offer the best guidance on different weight loss options and which medications may be best for you.