Semaglutide and dulaglutide are both once-weekly GLP-1 receptor agonists for type 2 diabetes, and they're often cross-shopped — Ozempic vs Trulicity. They share a mechanism and a weekly schedule, but differ most in weight-loss potency: in head-to-head trials semaglutide produced clearly greater weight reduction and A1c lowering, while dulaglutide remains a well-established option with strong cardiovascular outcome data.
At a glance
| Semaglutide | Dulaglutide | |
|---|---|---|
| Drug class | GLP-1 receptor agonist | GLP-1 receptor agonist |
| Brand names | Ozempic, Wegovy, Rybelsus | Trulicity |
| FDA status | Approved | Approved |
| Dosing | Once weekly injection (plus daily oral option) | Once weekly injection (single-use pen) |
| Weight loss | Greater (head-to-head) | More modest |
| Cardiovascular data | SELECT and others | REWIND outcomes trial |
| Main side effects | GI: nausea, diarrhea | GI: nausea, diarrhea |
The bottom line
Bottom line: For weight loss and glucose lowering, semaglutide has the edge in head-to-head data. Dulaglutide's draw is convenience (a simple no-assembly auto-injector) and a solid cardiovascular outcomes record. Both are approved, well-studied prescription GLP-1 drugs with the same GI-dominant side effects — the choice is clinical, not one-size-fits-all.
Frequently asked questions
Is semaglutide or dulaglutide better for weight loss?
In head-to-head trials semaglutide produced greater weight loss and A1c reduction than dulaglutide. Dulaglutide still lowers weight modestly and has strong cardiovascular outcome data. Both are prescription medicines.
Are Ozempic and Trulicity the same?
No. Ozempic is a brand of semaglutide and Trulicity is dulaglutide — different GLP-1 receptor agonists. Both are once-weekly injections for type 2 diabetes, but they are distinct molecules with different potency.
Do both have cardiovascular benefits?
Both have cardiovascular outcome trials supporting benefit in their studied populations — dulaglutide in REWIND and semaglutide in trials such as SELECT. Specifics differ; a clinician interprets which applies to a given person.
References
Combined peer-reviewed sources from both peptide guides. Inclusion is not endorsement.
- Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med. 2021. Peer-reviewed study
- Lincoff AM, Brown-Frandsen K, Colhoun HM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (SELECT). N Engl J Med. 2023. Peer-reviewed study
- Chao AM, Tronieri JS, Amaro A, et al. Semaglutide for the treatment of obesity. Trends Cardiovasc Med. 2023. Peer-reviewed study
- Smits MM, Van Raalte DH. Safety of Semaglutide. Front Endocrinol (Lausanne). 2021. Peer-reviewed study
- Davies M, Færch L, Jeppesen OK, et al. Semaglutide 2·4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2): a randomised, double-blind, double-dummy, placebo-controlled, phase 3 trial. Lancet. 2021. Peer-reviewed study
- Tan HC, Dampil OA, Marquez MM. Efficacy and Safety of Semaglutide for Weight Loss in Obesity Without Diabetes: A Systematic Review and Meta-Analysis. J ASEAN Fed Endocr Soc. 2022. Peer-reviewed study
- Gerstein HC, Colhoun HM, Dagenais GR, et al. Dulaglutide and cardiovascular outcomes in type 2 diabetes (REWIND): a double-blind, randomised placebo-controlled trial. Lancet. 2019. Peer-reviewed study
- Jendle J, Grunberger G, Blevins T, et al. Efficacy and safety of dulaglutide in type 2 diabetes: review of the AWARD phase 3 program. Diabetes Metab Res Rev. 2016. Peer-reviewed study
- Nicholls SJ, Pavo I, Bhatt DL, et al. Cardiovascular Outcomes with Tirzepatide versus Dulaglutide in Type 2 Diabetes. N Engl J Med. 2025. Peer-reviewed study
- Nicholls SJ, Bhatt DL, Buse JB, et al. Comparison of tirzepatide and dulaglutide on major adverse cardiovascular events in participants with type 2 diabetes and atherosclerotic cardiovascular disease: SURPASS-CVOT design and baseline characteristics. Am Heart J. 2024. Peer-reviewed study
- Pratley RE, Aroda VR, Lingvay I, et al. Semaglutide versus dulaglutide once weekly in patients with type 2 diabetes (SUSTAIN 7): a randomised, open-label, phase 3b trial. Lancet Diabetes Endocrinol. 2018. Peer-reviewed study
- Inagaki N, Takeuchi M, Oura T, et al. Efficacy and safety of tirzepatide monotherapy compared with dulaglutide in Japanese patients with type 2 diabetes (SURPASS J-mono): a double-blind, multicentre, randomised, phase 3 trial. Lancet Diabetes Endocrinol. 2022. Peer-reviewed study