Dual GIP/GLP-1 agonist · FDA-approved
A once-weekly, FDA-approved dual-action medication — the largest average weight loss of the approved options, around 21%.
✦ 2 min read · 2 sourcesWhat it is
Tirzepatide activates two gut-hormone pathways (GIP and GLP-1) rather than one. It is FDA-approved as Zepbound for chronic weight management (and obstructive sleep apnea in adults with obesity) and as Mounjaro for type 2 diabetes — the same drug. Once-weekly injection.
How it works
Like semaglutide it activates GLP-1, but it also activates GIP, a second hormone involved in appetite, blood sugar, and fat handling. The combined effect curbs hunger, slows stomach emptying, and increases fullness — the two-pathway design is thought to be why it tends to outperform single-pathway GLP-1 drugs.
What the evidence shows
In SURMOUNT-1 (adults with obesity, no diabetes), tirzepatide averaged ~21% weight loss at 15 mg over 72 weeks vs ~3% placebo. In SURMOUNT-5, the first head-to-head, it led to ~20% vs ~14% for semaglutide. Stopping treatment leads to substantial regain.
Quick check
Four questions, ~60 seconds, with a sourced result.
The honest take
FDA-approved prescription medicine
Status & safety
Prescription medicine. Side effects are predominantly gastrointestinal and usually mild-to-moderate during dose escalation. Rare serious risks include pancreatitis, gallbladder problems, and the same rodent-based thyroid-tumor boxed warning. Requires medical evaluation and monitoring.
Summaries of published, third-party research for educational purposes. Not medical advice; not a claim of efficacy or safety for any use.
New, plain-language summaries as the literature develops. Educational only — no products, nothing for sale.
GLP-1 receptor agonist · FDA-approved
A once-weekly, FDA-approved GLP-1 medication that helped adults lose roughly 15% of body weight on average in trials.
Read more →Triple GIP/GLP-1/glucagon agonist · Investigational
An investigational, not-yet-approved triple-action medication that produced the largest weight loss seen so far — up to ~25–30%.
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