Zepbound vs Ozempic is one of the most common comparisons Canadians search for when exploring GLP-1 medications for weight loss. Both drugs belong to the same class of injectable treatments, but they work differently, produce different results in clinical trials, and come at different price points. This guide breaks down everything you need to know about tirzepatide (Zepbound) and semaglutide (Ozempic) side by side, including clinical data, side effects, cost in Canada, and who each drug is best suited for.

Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or pharmacist before starting, stopping, or changing any medication. The information here reflects what was available at the time of writing and may change as new data or regulatory decisions become available in Canada.

What Are Zepbound and Ozempic?

Ozempic (semaglutide) and Zepbound (tirzepatide) are both injectable prescription medications in the incretin-mimetic family, used once weekly and originally developed for type 2 diabetes. They are now widely used for weight loss.

  • Ozempic is made by Novo Nordisk and contains semaglutide. In Canada, it is approved for type 2 diabetes. Its higher-dose weight-loss sibling is Wegovy, which uses the same molecule.
  • Zepbound is made by Eli Lilly and contains tirzepatide, the same active ingredient as Mounjaro (its diabetes brand). Zepbound is specifically branded and dosed for chronic weight management.

The key mechanistic difference: Ozempic targets GLP-1 only, while Zepbound targets both GLP-1 and GIP receptors. This dual action is believed to underlie the greater average weight loss seen with tirzepatide in trials.

Head-to-Head Comparison: Zepbound vs Ozempic at a Glance

| Feature | Zepbound (Tirzepatide) | Ozempic (Semaglutide) |

|---|---|---|

| Manufacturer | Eli Lilly | Novo Nordisk |

| Active Ingredient | Tirzepatide | Semaglutide |

| Mechanism of Action | Dual GIP/GLP-1 receptor agonist | GLP-1 receptor agonist |

| Administration | Once-weekly subcutaneous injection | Once-weekly subcutaneous injection |

| Available Doses | 2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, 15 mg | 0.25 mg, 0.5 mg, 1 mg, 2 mg |

| Primary Indication (Canada) | Chronic weight management (BMI ≥30, or ≥27 with comorbidity) | Type 2 diabetes (weight loss is off-label for Ozempic) |

| Health Canada Approval for Weight Loss | Approved for weight management (as Zepbound) | Not approved for weight loss (Wegovy is the weight-loss brand for semaglutide) |

| Pen Device | Single-dose prefilled pen | Multi-dose prefilled pen |

If you want molecule-specific deep dives, see our Ozempic guide, Mounjaro guide, and tirzepatide guide. For a direct semaglutide vs tirzepatide weight-loss comparison, see Wegovy vs Mounjaro.

How They Work: Single vs Dual Receptor Targeting

Ozempic (Semaglutide): GLP-1 Receptor Agonist

Semaglutide mimics GLP-1 (glucagon-like peptide-1), a hormone released after eating. It:

  • Increases glucose-dependent insulin secretion
  • Decreases glucagon
  • Slows gastric emptying
  • Enhances satiety signals in the brain

Result: you feel full sooner, stay full longer, and post-meal blood sugars are smoother.

Zepbound (Tirzepatide): Dual GIP and GLP-1 Receptor Agonist

Tirzepatide activates both GLP-1 and GIP (glucose-dependent insulinotropic polypeptide) receptors. GIP also influences insulin secretion, fat metabolism, and appetite.

By combining both actions in one molecule, tirzepatide has shown:

  • Greater average weight loss than GLP-1-only drugs
  • Strong glucose-lowering effects in people with type 2 diabetes

Key evidence: SURMOUNT and SURPASS trial programs (e.g., Jastreboff AM et al., NEJM 2022).

Clinical Trial Results: Weight Loss and A1C Reduction

Key Clinical Trials Compared

| Trial / Study | Drug | Average Weight Loss (%) | A1C Reduction | Duration | Notable Detail |

|---|---|---|---|---|---|

| SURMOUNT-1 | Tirzepatide 15 mg | 22.5% of body weight | N/A (non-diabetic) | 72 weeks | ~24 kg (52 lb) average loss |

| SURMOUNT-2 | Tirzepatide 15 mg | 14.7% of body weight | ~−2.1% | 72 weeks | Participants had type 2 diabetes |

| STEP 1 | Semaglutide 2.4 mg (Wegovy dose) | 14.9% of body weight | N/A (non-diabetic) | 68 weeks | ~15.3 kg (33.7 lb) average loss |

| STEP 2 | Semaglutide 2.4 mg | 9.6% of body weight | ~−1.6% | 68 weeks | Participants had type 2 diabetes |

| SURMOUNT-5 | Tirzepatide vs Semaglutide | 20.2% (tirzepatide) vs 13.7% (semaglutide) | Similar A1C reductions | 72 weeks | First major head-to-head trial |

In SURMOUNT-5, tirzepatide produced ~47% more relative weight loss than semaglutide over 72 weeks (Eli Lilly press release, 2024).

Even so, semaglutide’s ~15% average loss is also clinically powerful. The American Gastroenterological Association defines ≥5% loss as clinically meaningful.

Side Effects: Zepbound vs Ozempic

Both drugs share a similar side effect profile, dominated by gastrointestinal (GI) symptoms, especially during dose escalation.

Side Effects Comparison

| Side Effect | Zepbound (Tirzepatide) | Ozempic (Semaglutide) | Notes |

|---|---|---|---|

| Nausea | 24–33% (dose-dependent) | 15–20% | Most common; often improves after 4–8 weeks |

| Diarrhea | 17–23% | 8–10% | More frequent with tirzepatide |

| Vomiting | 9–13% | 5–9% | Dose-related for both |

| Constipation | 11–17% | 5–7% | Due to slowed gastric emptying |

| Abdominal pain | 5–8% | 5–7% | Similar rates |

| Decreased appetite | 11–20% | 6–9% | Expected therapeutic effect |

| Injection site reactions | 3–7% | 1–2% | Usually mild and transient |

| Fatigue | 3–5% | 3–5% | Similar |

| Pancreatitis (rare) | <1% | <1% | Seek urgent care for severe abdominal pain |

| Gallbladder events (rare) | 1–2% | 1–2% | Gallstones may occur with rapid weight loss |

Source: Health Canada product monographs for Zepbound and Ozempic.

Serious Warnings (Both Drugs)

  • Thyroid C-cell tumors (in animals): Avoid if you or a family member has medullary thyroid carcinoma or MEN2.
  • Pancreatitis: Stop the drug and seek care if you develop severe, persistent abdominal pain.
  • Hypoglycemia: Risk increases when combined with insulin or sulfonylureas.
  • Kidney injury: Can be precipitated by dehydration from severe GI symptoms.

Cost and Availability in Canada

Pricing and coverage are major practical differences for Canadians.

Cost & Coverage Snapshot (Approximate, 2026)

| Factor | Zepbound (Tirzepatide) | Ozempic (Semaglutide) |

|---|---|---|

| Monthly Retail Cost | ~$400–$550 CAD | ~$250–$350 CAD |

| Annual Cost (Approx.) | ~$5,000–$6,600 CAD | ~$3,000–$4,200 CAD |

| Provincial Drug Plan Coverage | Limited; variable, often for obesity specialists’ prescriptions | Commonly covered for type 2 diabetes |

| Private Insurance | Growing coverage for obesity; usually prior authorization | Widely covered for diabetes; weight-loss coverage varies |

| Pharmacy Availability | Increasing; supply stable in 2026 | Widely available; earlier shortages mostly resolved |

| Health Canada Status | Approved for chronic weight management | Approved for type 2 diabetes only |

| Generics | None | Yes, generic semaglutide ~$88-99/mo |

| Patient Support Programs | Lilly patient support program | Novo Nordisk NovoCare program |

For more detail, see our Ozempic cost and Mounjaro cost resources.

Worth noting on cost: since May 2026, generic semaglutide gives the Ozempic side a much cheaper option, roughly $88 to $99 per month at Costco Pharmacy versus Ozempic's $250 to $350 brand price. There is no generic tirzepatide, so Zepbound stays at full brand price. See our generic semaglutide guide.

Key nuance: Ozempic is usually only covered when prescribed for diabetes, not for weight loss alone. Zepbound has the obesity indication but is newer and not yet on all provincial formularies.

How Effective Is Each Drug Over Time?

Both medications work best as long-term treatments. Stopping them often leads to weight regain.

  • In the STEP 1 extension, people who stopped semaglutide regained about two-thirds of lost weight within 1 year (Wilding JPH et al., 2022).
  • Early tirzepatide data show similar trends: stopping the drug leads to gradual regain, though long-term discontinuation data are still emerging.

Implication: these drugs manage obesity as a chronic condition, similar to hypertension or dyslipidemia, rather than “curing” it.

Who Should Choose Which Drug?

Simplified Patient Selection Guide

| Patient Profile | Likely Better Choice | Rationale |

|---|---|---|

| Primary goal: maximum weight loss | Zepbound (tirzepatide) | Higher average weight loss (~20% vs ~15%) in trials |

| Type 2 diabetes + wants weight loss | Either (Ozempic or tirzepatide) | Both lower A1C; Ozempic has longer diabetes track record; Mounjaro is tirzepatide’s diabetes brand |

| Budget-conscious, no private insurance (with diabetes) | Ozempic | Lower cost and better provincial coverage for diabetes |

| Very sensitive to GI side effects | Ozempic | Slightly lower GI event rates |

| Needs an obesity-specific indication | Zepbound | Approved by Health Canada for chronic weight management |

| Previously on GLP-1 with limited results | Zepbound | Dual GIP/GLP-1 action may help non-responders to GLP-1-only drugs |

| High cardiovascular risk, no diabetes | Semaglutide (Wegovy/Ozempic molecule) | SELECT trial showed 20% reduction in major CV events; tirzepatide CVOT ongoing |

Cardiovascular Outcomes

  • Semaglutide (2.4 mg): SELECT trial showed a 20% reduction in major adverse cardiovascular events (MACE) in overweight/obese adults with established CVD but no diabetes (Lincoff AM et al., NEJM 2023).
  • Tirzepatide: SURPASS-CVOT is ongoing; definitive CV outcome data are not yet available.

Dosing and Titration Schedules

Both drugs use gradual titration to reduce GI side effects.

Zepbound (Tirzepatide) Typical Titration

  • Weeks 1–4: 2.5 mg once weekly
  • Weeks 5–8: 5 mg once weekly
  • Then increase by 2.5 mg every 4 weeks as tolerated
  • Usual maintenance: 5–15 mg once weekly (max 15 mg)

Ozempic (Semaglutide) Typical Titration

  • Weeks 1–4: 0.25 mg once weekly
  • Weeks 5–8: 0.5 mg once weekly
  • Then may increase to 1 mg, and up to 2 mg if needed and tolerated

Your prescriber may slow titration or hold at a lower dose if side effects are problematic.

Practical Considerations for Canadians

  • Prescriber access: Zepbound may be more commonly initiated by endocrinologists or obesity specialists; Ozempic is widely prescribed by family physicians for diabetes.
  • Supply: Earlier global GLP-1 shortages affected Ozempic more; by 2026, both are generally available, though local shortages can still occur.
  • Pharmacy stocking: Large chains (Shoppers, Rexall, Costco) typically stock both; smaller pharmacies may special-order Zepbound.
  • Storage & travel: Both require refrigeration before first use; in-use pens can usually be kept at room temperature (below ~30 °C) for a limited time—follow the specific product monograph when travelling.

Switching Between Zepbound and Ozempic

Switching is possible and increasingly common. Reasons include:

  • Inadequate weight loss on one agent
  • Side effects
  • Cost or coverage changes