If you have already read the Ozempic and Wegovy note, you know this shape. Mounjaro and Zepbound are the same drug — tirzepatide — from the same manufacturer. What differs is what each brand is approved to treat.

Same drug, different approval

Mounjaro is tirzepatide approved for type 2 diabetes. Zepbound is the same tirzepatide approved for chronic weight management, and in some patients for obstructive sleep apnoea.

Identical active ingredient — a dual GIP and GLP-1 agonist — sold under two labels.

Which is "for weight loss"?

Zepbound is the weight-indicated one and is typically what gets prescribed for that goal. Mounjaro is sometimes used off-label toward it but is a diabetes drug on paper.

As with semaglutide, coverage and availability usually settle which brand you actually get. That is not a clinical judgement, it is a formulary.

How it compares to semaglutide

Tirzepatide engages two gut-hormone receptors where semaglutide engages one, which is the usual explanation for why head-to-head trials generally show larger average weight loss for tirzepatide.

Average is doing real work in that sentence. The trade-offs — tolerability, cost, what your prescriber is willing to write — are individual, and the full comparison is worth reading before you decide you are on the wrong one.

What matters for you

Titrate at the pace you were given, hit the protein so what comes off is fat, manage the side effects, and track your own response.

Lean Protocol is a companion to the drug, not to the label on it. Educational, not medical advice — your prescriber chooses your medication, dose, and indication.