Compare
Side by side.
| Tirzepatide | Metformin | |
|---|---|---|
| Evidence | GRADE A | GRADE B |
| Category | GLP-1 | metabolic |
| Status | Rx | Rx |
| Typical cost | $400–$1,200 / mo | $5–$20 / mo |
| Mechanism | Activates both GIP and GLP-1 receptors, amplifying appetite reduction and insulin sensitivity. | Lowers glucose production by the liver and improves insulin sensitivity. It mildly affects mitochondrial energy signaling (AMPK), which may mimic some effects of caloric restriction. |
| Human evidence | SURMOUNT-1 showed ~20% average weight loss at the highest dose. Improvements in blood pressure, lipids and sleep apnea severity. Cardiovascular outcomes trials ongoing. | Observational data suggest diabetics on metformin may have outcomes comparable to non-diabetics. The TAME trial is designed to test aging outcomes but has not reported. Some data suggest it can blunt exercise adaptations in older adults. |
| Side effects | Nausea, diarrhea · Lean-mass loss · Gallbladder events | GI upset, diarrhea · Vitamin B12 deficiency with long use · Rare lactic acidosis (kidney impairment) |
Not medical advice — talk to a licensed clinician. Content is educational, reflects published literature, and is not a recommendation to start, stop or change any treatment.