Canadians in 2026 have four real prescription options for weight loss injections: semaglutide (Ozempic, Wegovy, and since May 2026 a much cheaper generic), tirzepatide (Mounjaro and Zepbound), and the older liraglutide (Saxenda). In the big trials, tirzepatide produced the most weight loss (about 21% at the top dose), semaglutide about 15%, and liraglutide about 8%.
The biggest change this year is price. Generic semaglutide now sells for roughly $88–$103 per pen at Canadian pharmacies, against roughly $400–$500 a month for brand Wegovy. A fifth drug, retatrutide, beat all of them in 2026 trials (up to 28.3% at 80 weeks) but is not approved anywhere yet. Here is the full comparison.
All options side by side
| Drug | Molecule | Approved for weight in Canada? | Average weight loss in main trial | Approx. cost |
|---|---|---|---|---|
| Wegovy | Semaglutide | Yes | ~15% at 68 weeks | ~$400–$500 / month |
| Ozempic | Semaglutide | No (type 2 diabetes) | Same molecule as Wegovy, lower doses | Varies by dose |
| Generic semaglutide | Semaglutide | Generic of Ozempic | Same molecule | ~$88–$103 / pen |
| Zepbound | Tirzepatide | Yes | ~21% at 72 weeks (top dose) | ~$300–$540 / month |
| Mounjaro | Tirzepatide | No (type 2 diabetes) | Same molecule as Zepbound | ~$300–$540 / month |
| Saxenda | Liraglutide | Yes | ~8% at 56 weeks | Daily injection; varies |
| Retatrutide | Retatrutide | No, investigational | Up to 28.3% at 80 weeks | Not available by prescription |
Prices are approximate Canadian pharmacy prices as of 2026 and vary by province, pharmacy and dose. Always confirm with your pharmacist.
How these drugs work
All of these drugs copy gut hormones that your body releases after eating. The main one is GLP-1 (glucagon-like peptide-1). GLP-1 tells your brain you are full, slows how fast your stomach empties, and helps your pancreas release insulin when blood sugar rises. Natural GLP-1 lasts only a couple of minutes in the blood; the drugs are engineered to last a day (liraglutide) or a full week (semaglutide, tirzepatide, retatrutide).
- Semaglutide and liraglutide act on one receptor: GLP-1.
- Tirzepatide acts on two: GLP-1 and GIP, a second gut hormone. That “dual agonist” design is the main reason it outperforms semaglutide.
- Retatrutide acts on three: GLP-1, GIP and glucagon. Glucagon raises energy expenditure and fat burning in the liver, which is why it is called a “triple agonist” and why its weight loss numbers are higher again.
For a deeper look at the three molecules, see retatrutide vs tirzepatide vs semaglutide.
Ozempic vs Wegovy: same molecule, different label
This is the most common point of confusion. Ozempic and Wegovy are the same drug, semaglutide, made by the same company, Novo Nordisk. The differences:
| Ozempic | Wegovy | |
|---|---|---|
| Approved for | Type 2 diabetes | Chronic weight management |
| Maximum labelled strength | Lower | Higher |
| Main trial | SUSTAIN (blood sugar) | STEP (weight loss) |
| Insurance coverage | Often covered for diabetes | Rarely covered |
Because Ozempic is often covered for diabetes and Wegovy rarely is, some people are prescribed Ozempic “off-label” for weight. That is a decision for a prescriber, and insurers increasingly require proof of diabetes before paying for Ozempic.
In the STEP-1 trial, people on the Wegovy dose lost an average of 14.9% of body weight over 68 weeks, compared with 2.4% on placebo (Wilding et al., 2021).
Generic semaglutide in Canada
Canada became the first major market to get generic semaglutide. Novo Nordisk’s Canadian data protection expired in January 2026, and Apotex launched Apo-Semaglutide in May 2026 as a generic of Ozempic. Other manufacturers have products under review with Health Canada.
- Price: pharmacy listings in 2026 range from about $88 to $103 per pen, with Costco pharmacies at the low end in several provinces.
- Is it the same? A generic must contain the same active ingredient and show it behaves the same way in the body. For a peptide like semaglutide, Health Canada reviews the generic’s purity and impurity profile closely.
- Can my pharmacist switch me? It depends on provincial interchangeability rules and whether your prescriber wrote “no substitution.”
If cost has kept you off semaglutide, the generic changes the math more than anything else in 2026. Ask your pharmacist whether it is listed in your province and what your plan covers.
Mounjaro and Zepbound (tirzepatide)
Same story as Ozempic and Wegovy, but from Eli Lilly: Mounjaro is tirzepatide approved for type 2 diabetes, and Zepbound is tirzepatide approved for weight management. Health Canada approved Zepbound in May 2025 and it reached Canadian pharmacies in July 2025.
In SURMOUNT-1, adults without diabetes lost an average of about 15%, 19.5% and 20.9% of body weight at the three tested doses over 72 weeks, compared with 3.1% on placebo (Jastreboff et al., 2022). That makes tirzepatide the most effective approved option in Canada today.
Pricing for Mounjaro and Zepbound is similar, roughly $300–$540 a month depending on strength and pharmacy, before any manufacturer support program. There is no generic tirzepatide in Canada yet.
Saxenda (liraglutide)
Saxenda was the first GLP-1 approved for weight in Canada. It is a daily injection rather than weekly, and it is less effective: about 8% average weight loss over 56 weeks versus 2.6% on placebo in the SCALE trial (Pi-Sunyer et al., 2015). Most people starting today are steered toward semaglutide or tirzepatide unless there is a specific reason for liraglutide.
Retatrutide: the next generation
Retatrutide is Eli Lilly’s triple agonist (GLP-1, GIP and glucagon). It is the drug behind most of the 2026 headlines:
| Trial | Who | Length | Average weight loss |
|---|---|---|---|
| Phase 2 (2023) | Obesity, no diabetes | 48 weeks | Up to 24.2% |
| TRIUMPH-1 (May 2026) | Obesity or overweight, no diabetes | 80 weeks | 19.0% / 25.9% / 28.3% by dose |
| TRIUMPH-1 extension | BMI 35+ | 104 weeks | 30.3% at the top dose |
| TRIUMPH-2 (July 2026) | Type 2 diabetes + obesity | 80 weeks | Up to 20.8% vs 4.0% placebo |
| TRIUMPH-3 (July 2026) | Severe obesity + heart disease | 80 weeks | Up to 22.6% vs 3.2% placebo |
Those numbers put retatrutide in the range of bariatric surgery for some people. The trade-off is more gastrointestinal side effects at higher doses (see below).
Retatrutide is not approved by Health Canada or the FDA and cannot be prescribed. Anything sold as retatrutide in Canada today is an unregulated research chemical, not a medicine. We track the approval timeline in is retatrutide approved? and the safety data in is retatrutide safe?
What it costs in Canada
| Option | Typical cash price | Rough yearly cost |
|---|---|---|
| Generic semaglutide | ~$88–$103 per pen | Lowest of all options |
| Wegovy | ~$400–$500 / month | ~$4,800–$6,000 |
| Zepbound / Mounjaro | ~$300–$540 / month | ~$3,600–$6,500 |
Two ways people lower the cost: shopping between pharmacies (warehouse-club pharmacies are often cheapest and do not require a membership for prescriptions in most provinces), and enrolling in the manufacturer’s patient support program, which can reduce the brand price.
Will insurance or my province pay?
- Provincial public plans generally do not cover drugs prescribed only for weight loss. Some cover semaglutide or tirzepatide for type 2 diabetes, with criteria that differ by province.
- Private workplace plans vary widely. Some cover Wegovy or Zepbound with prior authorization; many exclude weight-loss drugs entirely.
- Generic listings are still being decided province by province, so check your own formulary rather than assuming another province’s rules apply.
Side effects compared
All of these drugs share the same main side effects: nausea, diarrhea, constipation and vomiting, usually worst when starting or increasing the dose and easing over time. Rates rise with stronger drugs and higher doses.
| Trial (top dose) | Nausea | Vomiting | Stopped due to side effects |
|---|---|---|---|
| Retatrutide, TRIUMPH-1 (12 mg) | 42.4% vs 14.8% placebo | 25.3% vs 4.8% | 11.3% vs 4.9% |
| Tirzepatide, SURMOUNT-1 | About 1 in 3 | About 1 in 10 | About 6% |
| Semaglutide, STEP-1 | About 4 in 10 | About 1 in 4 | About 7% |
Less common but serious risks listed on the Canadian product monographs include pancreatitis, gallbladder problems, and a boxed-style warning about thyroid C-cell tumours seen in rodents, which is why these drugs are not used in people with a personal or family history of medullary thyroid cancer. Muscle loss along with fat loss is another real concern, which is why prescribers emphasize protein intake and strength training.
Who qualifies, and how to get a prescription
Wegovy and Zepbound are approved in Canada for adults with a BMI of 30 or more, or a BMI of 27 or more with at least one weight-related condition such as high blood pressure, type 2 diabetes, high cholesterol or sleep apnea, used alongside diet and exercise.
You can get a prescription from a family doctor, a walk-in clinic, an obesity medicine clinic, or one of several Canadian telehealth services that now specialize in GLP-1 prescriptions. Expect bloodwork and a medical history first, since these drugs are not suitable for everyone.
What happens when you stop
This is the least-discussed part. In the STEP-1 extension, people who stopped semaglutide regained about two-thirds of the weight they had lost within a year. Tirzepatide showed a similar pattern in SURMOUNT-4. The current medical view is that these drugs treat obesity as a chronic condition, more like blood pressure medication than a one-time course.
Where research peptides fit
Searches for “retatrutide Canada” and “tirzepatide peptide” have exploded because of the price gap between brand drugs and grey-market vials. To be clear about what TrueLabs sells: our retatrutide, tirzepatide and cagrilintide are research chemicals for laboratory use, tested by independent labs (COA library). They are not medicines, not approved for human use, and not a substitute for a prescription. If your goal is weight loss, the approved options above, and especially the new generic semaglutide, are the safe route, with a prescriber watching for side effects.
FAQ
Tap a question to reveal the answer.
What is the most effective weight loss injection in Canada?
Among approved drugs, tirzepatide (Zepbound) produced the most weight loss in trials, about 21% at the top dose over 72 weeks. Retatrutide produced more in 2026 trials but is not approved yet.
Is Ozempic the same as Wegovy?
Yes, both are semaglutide from Novo Nordisk. Ozempic is approved for type 2 diabetes and Wegovy for weight management at higher doses.
Is generic Ozempic available in Canada?
Yes. Apotex launched Apo-Semaglutide in May 2026 after Novo Nordisk’s Canadian data protection expired in January 2026. Pharmacy prices are roughly $88 to $103 per pen.
How much does Wegovy cost in Canada without insurance?
Roughly $400 to $500 a month at Canadian pharmacies in 2026, depending on the dose and pharmacy.
Is Zepbound available in Canada?
Yes. Health Canada approved Zepbound in May 2025 and it has been in Canadian pharmacies since July 2025, at roughly $300 to $540 a month.
Is retatrutide approved in Canada?
No. Retatrutide finished major phase 3 trials in 2026 but is not approved by Health Canada or the FDA. It cannot be legally prescribed.
Do provincial drug plans cover weight loss injections?
Generally not for weight loss alone. Some provinces cover semaglutide or tirzepatide for type 2 diabetes. Private plans vary, so check your own coverage.
Do you regain weight after stopping GLP-1 drugs?
Most people regain a large share of the weight. In the STEP-1 extension, people regained about two-thirds of their lost weight within a year of stopping semaglutide.
Related reading
- Retatrutide vs tirzepatide vs semaglutide
- Is retatrutide approved?
- Tirzepatide side effects
- What SURMOUNT and SURPASS showed
- Cagrilintide research guide
References
- Wilding JPH, Batterham RL, Calanna S, et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). N Engl J Med. 2021;384:989–1002. PubMed
- Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). N Engl J Med. 2022;387:205–216. PubMed
- Pi-Sunyer X, Astrup A, Fujioka K, et al. A randomized, controlled trial of 3.0 mg of liraglutide in weight management (SCALE). N Engl J Med. 2015;373:11–22. PubMed
- Jastreboff AM, Kaplan LM, Frías JP, et al. Triple-hormone-receptor agonist retatrutide for obesity: a phase 2 trial. N Engl J Med. 2023;389:514–526. PubMed
- Wilding JPH, Batterham RL, Davies M, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes Obes Metab. 2022;24(8):1553–1564. PubMed
- AJMC. Retatrutide achieves up to 30.3% average weight loss in phase 3 TRIUMPH-1 trial. May 2026. AJMC
- PharmExec. Retatrutide delivers up to 22.6% weight loss in two new phase III trials. July 2026. PharmExec
- GLP1Prices.ca. Generic Ozempic cost in Canada and Zepbound price and availability, 2026. GLP1Prices.ca
This article is general information, not medical advice. Talk to a doctor or pharmacist about whether any of these medicines is right for you. Prices are approximate and current as of October 2026. TrueLabs research compounds are sold for in vitro and laboratory research use only and are not intended for human or veterinary use.