Mounjaro (tirzepatide) and Trulicity (dulaglutide) are both weekly subcutaneous injections from Eli Lilly approved for type 2 diabetes. Mounjaro is a dual GIP/GLP-1 receptor agonist; Trulicity is a GLP-1 receptor agonist. Mounjaro produces greater A1C reduction and weight loss in indirect comparisons. Trulicity has a formal cardiovascular risk reduction indication based on the REWIND trial. Which is right for you depends on glycemic targets, weight goals, cardiovascular profile, and insurance coverage.
Side-by-Side Comparison
| Feature | Mounjaro | Trulicity |
|---|---|---|
| Generic name | Tirzepatide | Dulaglutide |
| Manufacturer | Eli Lilly | Eli Lilly |
| Mechanism | GIP + GLP-1 dual agonist | GLP-1 receptor agonist |
| FDA indication | Type 2 diabetes | Type 2 diabetes; CV risk reduction in T2D |
| Dose range | 2.5 to 15 mg weekly | 0.75 to 4.5 mg weekly |
| Frequency | Weekly SC injection | Weekly SC injection |
| Pen type | Single-dose pen (KwikPen-style) | Single-dose autoinjector with hidden needle |
| A1C reduction (max dose) | ~2.3 percentage points | ~1.5 percentage points |
| Weight loss (typical) | ~11–12 kg | ~3–4 kg |
| CV outcomes trial | SURPASS-CVOT (pending) | REWIND (12% MACE reduction) |
| CV trial population | — | Primary + secondary prevention |
| Approval year | May 2022 | September 2014 |
| List price/month | ~$1,070 | ~$1,000 |
| Boxed warning | Thyroid C-cell tumors | Thyroid C-cell tumors |
What Each One Is
Mounjaro (tirzepatide) is a once-weekly subcutaneous injection that activates two incretin receptors — GIP and GLP-1. The same molecule is also marketed as Zepbound for chronic weight management. Mounjaro was FDA-approved in May 2022 for type 2 diabetes. Read more on our tirzepatide overview.
Trulicity (dulaglutide) is a once-weekly subcutaneous injection that activates the GLP-1 receptor. The pen is a single-use autoinjector — the needle is hidden, and patients simply press the device against the skin and click. FDA-approved in September 2014 for type 2 diabetes. Read more on our dulaglutide overview.
Efficacy Comparison
There is no direct head-to-head trial between Mounjaro and Trulicity. However, indirect comparison using the SURPASS-1 (Mounjaro monotherapy in T2D) and AWARD trials (Trulicity various uses) provides reliable estimates of relative efficacy.
| Outcome | Mounjaro 5 mg | Mounjaro 10 mg | Mounjaro 15 mg | Trulicity 1.5 mg | Trulicity 4.5 mg |
|---|---|---|---|---|---|
| A1C reduction | ~1.9% | ~2.1% | ~2.3% | ~1.1% | ~1.5% |
| Weight loss (kg) | ~7.0 | ~9.0 | ~11.0 | ~2.7 | ~3.8 |
| A1C below 7.0% | ~80% | ~85% | ~88% | ~60% | ~70% |
Mounjaro produces approximately twice the weight loss and meaningfully greater A1C reduction across comparable potencies.
Mechanism Differences
- Both stimulate glucose-dependent insulin secretion, slow gastric emptying, suppress glucagon, and reduce appetite
- Mounjaro additionally activates the GIP receptor, which may amplify insulin secretion and improve adipose tissue insulin sensitivity
- Dulaglutide is structurally based on a modified GLP-1 fused to an immunoglobulin G4 Fc fragment, giving it a long half-life
- Tirzepatide is a 39-amino-acid peptide engineered to bind both incretin receptors
Cardiovascular Outcomes
Trulicity — REWIND (9,901 patients, 5.4-year follow-up) showed a 12 percent reduction in major adverse cardiovascular events. Notably, only about 31 percent of REWIND patients had established CVD — the rest had cardiovascular risk factors only — making REWIND the largest GLP-1 trial to demonstrate benefit in primary prevention.
Mounjaro — SURPASS-CVOT (largest cardiovascular outcome trial of a GLP-1 receptor agonist class) is ongoing with primary results expected 2025-2026. Preliminary safety data are favorable, but cardiovascular risk reduction is not yet a labeled indication.
When to Choose Mounjaro
- Greater A1C reduction or weight loss is desired
- Inadequate response to maximum-dose Trulicity
- Higher BMI patient where substantial weight reduction matters
- Insurance covers Mounjaro
When to Choose Trulicity
- Type 2 diabetes with cardiovascular risk factors but no established CVD — REWIND data are strongest here
- Established cardiovascular disease and patient or prescriber prioritizes formal CV indication
- Patient values the autoinjector pen with hidden needle (less needle anxiety)
- Moderate A1C reduction is sufficient
- Insurance covers Trulicity but not Mounjaro
- Longer real-world experience preferred
Side Effects (Both)
- Nausea — most common, peaks during dose titration
- Vomiting, diarrhea, constipation
- Abdominal pain, dyspepsia
- Decreased appetite
- Fatigue
- Injection site reactions
- Gallbladder issues (cholelithiasis, cholecystitis)
- Pancreatitis (rare)
- Acute kidney injury (dehydration-driven)
- Hypoglycemia when combined with insulin or sulfonylureas
- Boxed warning for thyroid C-cell tumors — contraindicated with personal/family history of medullary thyroid carcinoma or MEN 2
Dosing Schedules
Mounjaro — 2.5 mg weeks 1–4 → 5 mg weeks 5–8 → optional further increases to 7.5, 10, 12.5, 15 mg at 4-week intervals based on response and tolerability.
Trulicity — 0.75 mg weekly is the starting dose; can increase to 1.5 mg after 4 weeks; further escalation to 3 mg and 4.5 mg at 4-week intervals if needed for additional glycemic control.
Cost and Coverage
Both Mounjaro and Trulicity are Lilly products with similar pricing — Mounjaro at approximately $1,070 per month and Trulicity at approximately $1,000 per month. Insurance coverage varies by formulary. Lilly increasingly prioritizes Mounjaro coverage, and some plans now prefer Mounjaro over Trulicity for new starts. Manufacturer savings cards can lower commercial copays for both.
Switching Between Them
Switching is typically straightforward — discontinue Trulicity and start Mounjaro at 2.5 mg weekly the following week, titrating monthly. Patients fully tolerating Trulicity 1.5 mg or higher may start Mounjaro at 5 mg under physician guidance, though most clinicians err on the side of slow titration to limit GI side effects. No washout period is required.
Lifestyle Pairing
Both medications work best alongside diet and physical activity. Read more about diet for blood sugar and A1C goals.
The Bottom Line
Mounjaro produces greater A1C reduction and weight loss than Trulicity, owing to its dual GIP/GLP-1 mechanism. Trulicity has the easier injection device — an autoinjector with hidden needle — and a cardiovascular outcomes trial that demonstrated benefit in patients with risk factors only, not just established disease. Side effect profiles are similar. Cost is comparable. Talk to your doctor about which fits your goals; both are reasonable options for many patients with type 2 diabetes needing more than metformin.
