The Four Peptides Everyone Starts With

The short version

Peptides are short chains of amino acids — the same building blocks that make up every protein in the body, just far smaller. Some peptides, like Ipamorelin, are made in a lab to mimic and nudge the body's own hormone signals. Others, like NAD+, are things every single cell already produces and cannot survive without. A couple of the compounds here, Semaglutide and Tesamorelin, have already gone through the full clinical-trial process and become approved prescription medicines for specific, narrow uses.

This site is a plain-English field guide to four of the research peptides people ask about most: Ipamorelin, NAD+, Semaglutide, and Tesamorelin. Each has its own page that opens with a short, jargon-free explanation of what the compound is, then goes deeper into the mechanism, the published research, and the safety picture — with the technical detail added on top, not left out. Nothing on this site recommends a dose for anyone to take, and no page here is a substitute for a conversation with a licensed clinician.

Why these four, together

These four compounds do not share a drug class, a mechanism, or even a level of regulatory approval — and that is exactly the point. Ipamorelin is a research peptide that has never been approved as a drug anywhere. NAD+ sits in a gray zone between a naturally occurring cell metabolite and a marketed supplement or IV-therapy ingredient. Semaglutide and Tesamorelin are both FDA-approved medicines, but for very different, very specific reasons — one for metabolic disease and weight management, the other for a single form of HIV-related fat redistribution.

What ties them together is simpler than a shared mechanism: they are the core research peptides readers ask about most. Between them they cover the growth-hormone axis (Ipamorelin and Tesamorelin), cellular energy metabolism (NAD+), and incretin/metabolic signaling (Semaglutide) — a cross-section broad enough to answer most of the questions a newcomer to this space is likely to bring. NAD+ leads this guide because it is the compound with the widest general audience and the least specialized starting knowledge required.

What are research peptides?

"Research peptide" is a loose umbrella term, and this guide tries to use it honestly rather than loosely. At one end are compounds like Ipamorelin — short, synthetic peptides sold explicitly as laboratory research chemicals, never approved by a regulator for human use, and studied mostly in cells and animals. At the other end are Semaglutide and Tesamorelin, which started life as research compounds and are now fully approved prescription drugs with large human trial programs behind them. NAD+ occupies its own middle ground: a molecule the body already makes, sold both as an over-the-counter supplement and, in some clinics, as a compounded injectable.

Because these compounds sit at such different points on the spectrum from "unregulated research chemical" to "approved medicine," this guide treats that distinction as one of the most important facts about each one — not a footnote. Every page states plainly whether a compound is approved, for what, and how far the human evidence actually reaches.

How to read this guide

Each compound page follows the same shape: a short plain-English summary first, then what the compound is chemically, how it works in the body, what the published research actually found (with citations), and what people report anecdotally alongside the cited safety cautions. The compare page lines up all four side by side on the dimensions that matter most — regulatory status, evidence base, and the single biggest caution for each. The FAQ answers the specific questions people bring to this topic most often, and the references page collects every source cited across the whole site in one place.