A plain-language, continually updated guide from Dr. Matt Chalmers’ clinical reference on hormones and peptides.
Retatrutide is a triple agonist — it activates the GLP-1, GIP, and glucagon receptors all at once, adding a third pathway on top of what Semaglutide and Tirzepatide already do. That glucagon piece is what genuinely sets it apart: it’s the first compound in this drug class shown to meaningfully raise your resting metabolic rate, not just reduce how much you eat. Our reference material frames it simply — GLP-1 asks “have we eaten enough?”, GIP asks “where should nutrients go?”, and glucagon asks “how do we burn more energy?” Retatrutide answers all three at once.
In its Phase 2 trial (published in the New England Journal of Medicine, 2023), it produced an average 24.2% weight loss at 48 weeks. Interim Phase 3 TRIUMPH trial data has shown 28.7% at the 12 mg dose and 26.4% at 9 mg, with 9 mg emerging as the preferred balance of results and tolerability. An FDA filing is expected sometime in late 2026 or 2027.
“As of July 2026 this is by far my favorite peptide. The metabolic change this is allowing will change the world. I am watching diabetes, dementia, PCOS, endometriosis, fatty liver, sleep apnea and lots of other things tied to insulin resistance, just melt away. It is important that you maintain the environment for this though.”
— Dr. Matt Chalmers, The Pillars Path: A Root-Cause Guide to Hormones, Peptides, and Metabolic Health
Retatrutide’s glucagon-driven fat-burning is significant enough that our reference material treats its nutrient needs as the highest priority in this entire drug class. Acetyl-L-carnitine is considered the single most critical addition, since glucagon mobilizes large volumes of fatty acids that require carnitine to actually enter the mitochondria for burning. Protein needs are also elevated (1.6–2.0 g per kg of body weight, with resistance training, is the recommended minimum), since the glucagon receptor raises the risk of muscle breakdown alongside fat loss. B vitamins, CoQ10, alpha-lipoic acid, and magnesium all matter more here too, given the increased metabolic throughput.
Retatrutide remains in Phase 3 clinical trials and is not FDA-approved for any indication. An FDA filing is anticipated in late 2026 or 2027 based on current trial timelines. It is not currently available for prescribing or compounding outside of a clinical trial. This page is provided for educational purposes only, in anticipation of possible future approval, and is not an offer to provide Retatrutide at this time.
Yes, it has in clinical trials. Weight loss needs to be defined. Losing fat is good; losing muscle is bad. When you use these tools, you need to track your progress and make sure the weight you’re losing is fat, not muscle. If your provider isn’t working on your testosterone, protein intake and exercise, you’re not getting the care I believe you need.
Retatrutide has GLP-1, GIP and glucagon. Glucagon tells the body to use fat as a fuel source, and it can help hold insulin levels down. That can be a big advantage when you are trying to fix insulin resistance, which often leads to problems like diabetes, dementia, PCOS, endometriosis, PMS, heart attack and stroke, to name a few.
Not yet. We expect it to become available in mid-2027.
Early trial results suggest that, because of its glucagon component, retatrutide may be much better at improving insulin resistance than semaglutide or tirzepatide.
The same ones we see with all GLP-1s, though a little less often. Depending on your body, the most common are nausea, skin tingling, burping, hair loss and loose stools. More serious problems, like pancreatitis, are rare, and the common ones are easy to control. We dose differently than most clinics: we dial in the dose for you specifically, so you stay at a level of nausea you can tolerate. If that is none, that’s fine. If you want to feel it, but just barely, that’s up to you too.
Learn more about the receptor that sets Retatrutide apart: Glucagon. Compare with Semaglutide and Tirzepatide.
Learn about our Metabolic Reset program, which addresses insulin resistance, sleep, and hormones together.
This page draws on The Pillars Path: A Root-Cause Guide to Hormones, Peptides, and Metabolic Health by Dr. Matt Chalmers — Pillars of Wellness’ clinical reference on hormone and peptide therapy.
