Three generations. Different questions.

A receptor is a part of a cell that receives a signal. An agonist is a compound that activates a receptor. GLP-1, GIP and glucagon are names for hormone signals. Our generation labels count receptor types; they are not official approval categories.

FDA-approved

The U.S. Food and Drug Administration has reviewed a specific medicine. FDA-approved semaglutide and tirzepatide products exist. The ingredient name alone does not carry that approval.

Compounded

Made to order. Compounded semaglutide and tirzepatide are not FDA-approved. The FDA does not review their safety, quality or effectiveness before they are sold.

Investigational

Still being studied. Retatrutide is in Phase 3 clinical trials, which are studies in people. It is not FDA-approved and is not available by prescription.

One, two and three make the designs easier to understand. They do not prove that a compound is safer or more suitable for a person. They do not answer questions about other medicines, medical history or follow-up.

The status of the actual product matters too. An approved product, a compounded medicine and a research-only product are different categories even when a familiar compound name appears on the label.

Research-only products may be marked “not for human use.” No one reviews your health as part of that order. The FDA warns that products sold under research labels can be of unknown quality and may be harmful.

Questions for a provider include which product is being considered, whether it is an approved product or a medicine made to order, and what follow-up would be arranged. A preference for a generation does not settle those questions.

Promise prescribes semaglutide and tirzepatide now through licensed U.S. providers. A provider reviews every request and decides whether to prescribe. Not everyone qualifies.

A licensed U.S. provider reviews each request and makes the prescription decision. A product choice does not guarantee a prescription.

Promise is for U.S. patients only. Availability varies by state and by treatment.

Promise has no retatrutide product. Its links here are for metabolic support, semaglutide or tirzepatide. They are not a route to retatrutide.

1. FDA: what compounding means

   Explains medicines made to order and how they differ from FDA-approved products.

2. FDA: concerns about unapproved GLP-1 drugs

   Covers unapproved products, including retatrutide, sold with research-only labels.

3. Semaglutide: approved product information

   Records the GLP-1 target and the status of a specific approved semaglutide product.

4. Tirzepatide: approved product information

   Records the GIP and GLP-1 targets and the status of a specific approved tirzepatide product.