What it is
Tirzepatide is a weekly injection that copies two gut hormones, GIP and GLP-1. Mounjaro is the brand for type 2 diabetes, and Zepbound is the brand for weight management and sleep apnea.
By acting on both hormone receptors, it helps the body release insulin when blood sugar rises, slows stomach emptying, and reduces appetite. Most people feel full sooner and have fewer food cravings.
US regulatory status
FDA-approved. Mounjaro is approved for type 2 diabetes and, since August 2026, to lower cardiovascular risk in adults with type 2 diabetes and heart disease; Zepbound is approved for chronic weight management and for moderate-to-severe obstructive sleep apnea in adults with obesity. The FDA has warned consumers about unapproved and counterfeit tirzepatide products.
What the research shows
Tirzepatide is backed by large phase 3 programs (SURPASS for diabetes, SURMOUNT for weight, SURMOUNT-OSA for sleep apnea, SURPASS-CVOT for heart outcomes). In these trials it lowered A1C, produced substantial weight loss compared with placebo, and reduced sleep apnea severity. Like other drugs in this class, weight tends to return after it is stopped.
How it is given
Weekly subcutaneous injection (single-dose pen, multi-dose pen or vial)
Commonly reported side effects
- Nausea
- Diarrhea
- Vomiting
- Constipation
- Decreased appetite
- Injection site reactions
Questions to ask your provider
- Is this medicine a good fit for my health history, including any thyroid, pancreas, gallbladder or kidney problems?
- How should I handle stomach side effects, and which symptoms mean I should call you right away?
- Does this interact with my other medicines, especially insulin, sulfonylureas or birth control pills?