Mounjaro vs Zepbound: What's the Difference?
Matt · May 24, 2026
Mounjaro and Zepbound are both made by Eli Lilly and both contain tirzepatide, a dual GIP and GLP-1 receptor agonist. The difference is regulatory: Mounjaro is approved for type 2 diabetes, Zepbound is approved for weight loss and obstructive sleep apnea in adults with obesity. The pen, the dose strengths, and the mechanism are otherwise identical.
Same Drug, Different Labels
If you compare the prescribing information side by side, the molecule is the same. Both come as pre-filled single-dose pens at 2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, and 15 mg. Both are injected subcutaneously once a week. Both follow the same titration schedule starting at 2.5 mg.
What changes is the label indication, which affects insurance coverage. Many users report their insurer will cover Mounjaro if they have a type 2 diabetes diagnosis but deny Zepbound for weight loss alone. Others see the opposite — a plan that covers Zepbound under their weight management benefit but not Mounjaro. Coverage rules vary widely, so it's worth checking with your insurer before starting either.
Cost and Access Differences
Without insurance, the list price of both is similar — typically over $1,000 per month. Lilly runs a self-pay program called LillyDirect that offers Zepbound vials (not pens) at lower price points, currently around $349–$499 per month depending on dose. Mounjaro does not have an equivalent vial program.
During the FDA-declared shortage, compounded tirzepatide was widely available through telehealth clinics. The FDA removed tirzepatide from the shortage list in late 2024, which limited compounding pharmacies' ability to produce it. Many people who started on compounded versions have since switched to branded Zepbound or Mounjaro.
Which One Should You Track?
If your doctor prescribed tirzepatide, the brand name doesn't change how you should track your response. The things that matter are dose, injection date, injection site, side effects, weight trend, and any lab values your provider is watching (A1C if diabetic, lipids, liver enzymes).
Trace lets you log all of this in one place without sending your health data to a server. You can mark each weekly injection, rotate sites between abdomen, thigh, and upper arm, and note side effects like nausea or fatigue. If you bump up doses on the titration schedule, the app keeps a clean timeline of when each change happened — useful context for your next appointment.
Frequently Asked Questions
Can I switch from Mounjaro to Zepbound at the same dose?
Many users report switching without re-titrating because the molecule is identical. Talk to your prescriber before swapping, since insurance and pharmacy logistics may require a new prescription even when the dose stays the same.
Is Zepbound more effective for weight loss than Mounjaro?
No. They are the same drug. The clinical trials behind Zepbound's weight-loss approval (SURMOUNT) used the same tirzepatide used in Mounjaro's diabetes trials (SURPASS). Any difference you see between two patients comes down to individual response, not the brand.
Does Zepbound treat sleep apnea?
The FDA approved Zepbound in late 2024 for moderate-to-severe obstructive sleep apnea in adults with obesity, based on the SURMOUNT-OSA trial. Research suggests the benefit comes from weight loss reducing airway obstruction. Discuss with your doctor whether this applies to your situation.