Semaglutide vs. tirzepatide

Weight management medications have gained significant attention recently for their potential to support weight loss. While semaglutide has become a popular option, there are also other options, including tirzepatide, when exploring treatments.

If you’re interested in these medications or simply want to learn more about them, it’s crucial to have accurate information. Here are some details about the differences, similarities and considerations for both semaglutide and tirzepatide.

How does semaglutide work and what are its key benefits?

Both semaglutide and tirzepatide are glycemic controlling medications. But, while they’re prescribed for some of the same uses, they have important differences. 

Semaglutide is a type of medication known as a glucagon-like peptide-1 receptor agonist (GLP-1 agonist).

GLP-1 agonists mimic the hormone GLP-1 that your body produces naturally to stimulate your pancreas to release insulin. Insulin helps to reduce blood sugar levels, which is why GLP-1s are used to treat type 2 diabetes. 

Beyond affecting your insulin levels, GLP-1 agonists also slow down your digestion, leaving you feeling fuller, longer. GLP-1s also target areas of the brain that control hunger. It reduces appetite, increases the sensation of fullness, and slows down how quickly food leaves the stomach. These effects help individuals reduce food intake and lose weight over time.

How is tirzepatide different from semaglutide?

Tirzepatide is also a GLP-1 agonist. However, tirzepatide also mimics an additional hormone called glucose-dependent insulinotropic polypeptide (GIP for short).

GIP stimulates your pancreas to release insulin. And, like GLP-1 agonists, this reduces blood glucose levels and promotes feelings of fullness. However, new research suggests GIP adds another feature by also increasing your energy expenditure so you burn more calories.

Weight loss with semaglutide vs. tirzepatide

If your doctor prescribes a semaglutide or tirzepatide-based drug to help you with weight loss, both semaglutide and tirzepatide may be effective. A large study comparing the two showed that most participants lost at least 5% of their starting body weight.

Despite this, there was a clear difference. Over 12 months, 87.8% of participants taking tirzepatide lost 5% or more of their starting weight vs. 71.8% of those taking semaglutide.

Over the same time, 66% of the tirzepatide group lost 10% or more of their initial weight, while only 41.1% of the semaglutide group reached that threshold.

Finally, at the one-year mark, 44.5% of the tirzepatide participants achieved 15% or greater total weight loss vs. only 19.7% of those on semaglutide. So, while both groups experienced meaningful weight reductions, those taking tirzepatide lost significantly more, according to this study.

Common side effects for both medications

Since both tirzepatide and semaglutide affect the gastrointestinal tract, it’s unsurprising that their most common side effects involve digestive issues. These may include:

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

Less commonly, these medications can cause more severe effects such as hypoglycemia (a sudden drop in blood sugar levels), especially if taken with other diabetes medication such as insulin. These medications can also cause pancreatitis, or inflammation of the pancreas. 

Serious risks and warnings associated with tirzepatide

While most individuals who use these medications don’t experience serious complications, they can occur. Both medications have been shown to cause thyroid tumors in rodents. As a result, anyone with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2 shouldn’t take them.

You should also avoid them if you’re pregnant or breastfeeding, as they haven’t been studied in these populations. 

Besides these risks, both tirzepatide and semaglutide may also increase the risk for gallbladder or biliary diseases, even without type 2 diabetes or obesity. And, because tirzepatide slows the movement of food through your gastrointestinal system, it can affect the absorption of oral medications. This can cause medications like the birth control pill and Warfarin to become less effective.

It’s important to speak to your doctor about risks, as certain brands of semaglutide drugs may increase heart rates, which may be an issue in people with uncontrolled hypertension, or on ADHD or asthma medications.

Comparing the cost between semaglutide and tirzepatide

In Canada, tirzepatide generally ranges between $300 – $450 for a four-week supply depending on your dose. 

In contrast, Canadians can expect to pay somewhere between $200-300 for a month’s supply of semaglutide drugs. 

Insurance coverage and financial assistance options

In Canada, tirzepatide) is available as a diabetes medication; however, it’s not covered by provincial or territorial health insurance plans.

In contrast, semaglutide is covered as a diabetes medication under some provincial and territorial plans. Despite this, its use is often restricted and it doesn’t receive the same coverage in its weight-loss form.

You’re more likely to receive coverage for both medications through third-party providers like private or employer insurance plans — with an important caveat. In Canada, weight loss is considered an “off-label” use of tirzepatide. Consequently, insurance plans are unlikely to cover it unless patients are also diabetic.

If you don’t have private insurance, you may qualify for savings on tirzepatide through its manufacturer, provided you have diabetes and are over 18.

Who should consider semaglutide or tirzepatide?

In Canada, most tirzepatide and semaglutide drugs are approved to treat type 2 diabetes. As a result, patients must be 18 years or older and:

• Have type 2 diabetes and a BMI of 30 or more
• Have type 2 diabetes and a BMI of 27 with one or more weight-related health conditions.

However, under the brand name Wegovy, semaglutide is also approved to treat weight loss in Canada. In this case, it’s available to individuals without diabetes who:

• Have a BMI of 30 or more
• Have a BMI of 27 and one or more weight-related conditions
• Children between 12 and 18 who meet these criteria

How to decide with your doctor

Given potential drug interactions and health complications, it’s crucial that your healthcare provider has a complete picture of your health, including any history of eating disorders, kidney or digestive issues. You should also inform your provider of any prescription or OTC medications.

Together with your goals and lifestyle, your specific profile will help your provider decide if weight-loss medication is a good fit, what your dosage and check-in frequency should be or if you should consider another alternative instead.

Long-term health benefits beyond weight loss

Medications like semaglutide and tirzepatide can take some of the struggle out of losing weight and maintaining that change.  However, they may also induce other long-term health benefits as well.

Improving metabolic health with semaglutide

Studies have shown that in additional to weight loss semaglutide can have a measurably beneficial effect on metabolic health by:

• Reducing fasting blood glucose
• Lowering blood pressure
• Decreasing waist circumference
• Reducing LDL (“bad”) cholesterol

Tirzepatide’s role in cardiovascular health

Individuals with excess weight or obesity are at increased risk of other health issues, especially heart disease. While its weight loss and blood sugar control benefits can help with this, studies show that tirzepatide may produce additional cardiovascular benefits.

While both tirzepatide and semaglutide help with cardiovascular health, tirzepatide is generally considered more effective. Tirzepatide works by lowering HbA1c — a marker of long-term blood glucose levels — better than either semaglutide or insulin. It also increases good cholesterol (HDL) while simultaneously contributing to a reduction in bad cholesterol (LDL) and triglycerides. 

Inflammation is also affected by tirzepatide, which lowers markers of inflammation within the body. Given these effects, it’s perhaps unsurprising that tirzepatide may substantially lower the risk of adverse cardiovascular effects in individuals who are overweight or obese.

Can you switch between semaglutide and tirzepatide?

Yes, you can switch from semaglutide to tirzepatide (and vice versa). However, while switching is possible, you may not have the same amount of coverage through provincial or private insurance plans. Make sure you understand your coverage options before asking your doctor to change medications.

How quickly can you expect results?

Both semaglutide and tirzepatide are titrated, which means you begin them at low doses and increase until you achieve either your optimal or the maximum dose. Because of this, results differ from person to person.

While some report appetite suppressing effects within days to weeks, research indicates it takes around 16 weeks to lose 5% of total body weight on tirzepatide 5mg and 24 weeks on semaglutide 1mg, in conjunction with diet and exercise plans. 

These are averages, however, and your individual results may differ. 

Making an informed choice

Funding through provincial plans differs for the drugs and not all private insurance plans cover both. And, depending on your health and family history they may not be appropriate for you. If you’re exploring weight-loss medication, your first step should be to speak to a healthcare provider to determine the best fit for you.

Weight management is a personal journey, and medications like semaglutide and tirzepatide may be options for some individuals. However, treatment decisions should always be made in consultation with a qualified healthcare professional.

Curious about weight loss medication? Maple members in Ontario now have complimentary access to our Weight Medication Assessment, part of our comprehensive Weight Health program. This program offers a holistic approach to weight management, connecting eligible patients with Canadian-licensed primary care providers who may prescribe GLP-1 medications, including needle-free options, where appropriate. Guided by medical expertise, it provides a supportive and patient-centred path toward your weight health goals.

Currently, the Weight Health program including GLP-1 medications is only available in Ontario, but we’re working to expand soon. Maple members across Canada can still access many expert-led weight health services tailored to their needs, including medical weight coaches, mental health therapists, sleep therapists and registered dietitians — each offering personalized support for your weight health journey.

If you’re considering weight management medications or want to explore your options, speak with your doctor. They can provide personalized guidance based on your health history, medical needs, and treatment goals.

The information presented here is for educational purposes and is not meant to replace the advice from your medical professional. When using virtual care, all medical treatment is at the sole discretion of the provider. Virtual care is not meant for medical emergencies, and your provider will determine if your case is appropriate for virtual care. If you are experiencing an emergency like chest pain or difficulties breathing, for example, please call 911 or go to your nearest emergency room.