The complete guide to peptides. What they are, what they do, who they're for — in plain language, not textbook.
Reference · 2026 Edition
Think of your body as a city full of cells, all talking to each other constantly. Peptides are the text messages. Short, specific, fast. They tell cells when to grow, when to repair, when to release a hormone, when to feel hungry, when to feel full.
Your body already makes thousands of peptides on its own. The ones in this catalogue are lab-made versions of those natural signals. Some copy a signal exactly. Others last longer or bind more strongly. They're powerful, and worth taking seriously.
A peptide arrives, finds its receptor, locks in, and triggers a response inside the cell.
Most peptides can't survive stomach acid. So they're delivered as a shot, a nasal spray, or a cream. Digestion gets skipped entirely.
Each peptide is built to dock onto a specific spot on a specific cell. A key fitting one lock. Weight-loss peptides find appetite cells. Healing peptides find injured tissue.
Once docked, the peptide tells the cell what to do. Release a hormone. Slow digestion. Build new tissue. Calm inflammation. The cell follows the instruction.
The body breaks them down quickly. Minutes to hours. How fast they clear is what sets the dosing schedule. Some are engineered to last days.
Every peptide here falls into one of six groups, sorted by what it actually does. Tap a category to jump to those entries in the index.
Searchable, filterable, with full breakdowns for each. What it is. How it works. What it's used for. Below — the four most-searched, as a starting point.
Three years ago, peptide access meant convincing a primary-care doctor to write a prescription, or buying gray-market vials online. Today the dominant path is telehealth — and the category has fragmented into three distinct lanes worth understanding before you pick one.
In-depth comparisons and analyses on the most-searched questions about peptides — sourced, currently dated, and built to be the page you forward to a friend.
The 9 questions most patients don't think to ask before starting a GLP-1 — and what the right answers sound like. Built to bring to the appointment.
Three years ago, peptide access meant a primary-care prescription or gray-market vials online. Today, telehealth is the default — fragmented into three recognizable lanes with very different economics and clinical depth. Here's the field guide.
The two most-searched recovery peptides on the consumer internet. Both have extensive animal research. Both have almost no published human clinical trials. Here's what the science actually says — and what gym forums get wrong about both.
The FDA shortage exception that legalized compounded Ozempic and Mounjaro ended in 2025. As of April 30 2026, the FDA has formally proposed permanently closing the door — for both 503A pharmacies and 503B outsourcing facilities. So why are clinics still selling it?
The three biggest weight-loss drugs of the 2020s pull different sets of metabolic levers — one, two, and three respectively. The differences in the trial data are larger than most articles will tell you. Here's the comparison, sourced and current.
New to this or already mixing your first vial. Both answers live behind one of these buttons.
A quick orientation. Most peptides ship as vials and follow the syringe routine. A few come as pre-filled pens — easier, but only available for select compounds.
The vial of peptide. Bacteriostatic water. Insulin syringes. Alcohol swabs. A sharps container for safe disposal.
Pull bacteriostatic water into a syringe. Slowly inject it into the vial along the side. Swirl gently. Don't shake. The powder dissolves.
Pull the calculated amount into a clean insulin syringe. Tap to bring air bubbles to the top. Push them out before injecting.
Most peptides are subcutaneous — into the soft fat of the belly or thigh. Clean the spot. Pinch the skin. Insert at 90°. Push slowly. Withdraw.
Reconstituted vials go in the fridge. Use within 30 days. Drop used syringes into a sharps container — never in regular trash.
A growing number of peptides now ship as pre-filled, pre-dosed pens. Click a dial. Press a button. The reconstitution-and-syringe routine — gone, for these.
Easier. No mixing, no math, no syringe handling. Significantly lower barrier to consistent dosing.
Safer. Pre-measured doses eliminate calculation errors. The needle is built in, sterile, and shielded.
Pricier. Convenience costs more per dose than vials — often substantially more.
Limited menu. Only some peptides come in pen form. Most research peptides still ship as vials.
This is general orientation, not medical instruction. Specific peptides have specific protocols. Always work with a doctor who knows what you're using.
Quick answers to the questions that come up most. The full reference covers each peptide in more depth.
Prescription peptides like Ozempic or Wegovy are FDA-approved drugs. You get them from a pharmacy with a doctor's prescription. They've been through clinical trials. They're produced under strict pharmaceutical standards. They're legal to use as prescribed.
Research-grade peptides are sold "for research purposes only." Meaning produced for laboratory use, not human use. They're widely available online but exist in a legal gray area. Quality varies significantly between sources.
It depends on which one and how you're getting it. FDA-approved peptides through a licensed prescriber and pharmacy are fully legal. Research-grade peptides sit in a gray zone. They're sold legally for research use. Using them on yourself is technically off-label and unregulated.
The FDA's compounding policy on peptides has been moving fast. In April 2026 the FDA removed twelve peptides — including BPC-157, TB-500, GHK-Cu (injectable), MT-2, KPV, MOTS-c, DSIP, Epitalon and Semax — from Category 2 of the interim 503A bulks list. CJC-1295 was removed earlier (September 2024). Removal does not mean approval. The Pharmacy Compounding Advisory Committee (PCAC) is reviewing these substances starting July 2026 and will recommend whether each can be added to the 503A Bulks List for compounding. PCAC has previously voted against CJC-1295, ipamorelin, and thymosin alpha-1.
Last reviewed: May 18, 2026. Each peptide entry has its own regulatory status.
Steroids are synthetic versions of hormones, mostly testosterone. Peptides are short chains of amino acids that act as signaling molecules. They tell your body what to do. They don't replace a hormone directly.
A growth hormone peptide like Sermorelin tells your pituitary to release more of your own growth hormone. Direct HGH injections are synthetic hormone replacement. Different mechanism. Different risk profile. Different legal status.
For prescription peptides, yes. You'll need a doctor or telehealth provider to write the prescription. Many telehealth services now specialize in peptides.
For research-grade peptides, no doctor is involved in the purchase. But that doesn't mean a doctor isn't a good idea. Working with someone who knows your bloodwork and medical history is the difference between informed experimentation and gambling with your body.
Start with the goal, not the compound. Body composition? Recovery from injury? Sleep? Focus? Skin? Each goal has a small set of peptides associated with it.
The Find your match tool walks you through 5 questions and recommends peptides matched to your goal and comfort level. Or browse the full catalog sorted by category.
Most research-grade peptides ship as a freeze-dried powder in a vial. Before you can use them, you mix the powder with bacteriostatic water. That turns it into a liquid you can draw into a syringe. The mixing step is called reconstitution.
Getting the math right matters. Too much water and your dose is too dilute. Too little and you can't draw it accurately. The built-in calculator does the math for you.
Everything on this site is for learning, not for treating yourself. Nothing here is a recommendation to use, buy, or inject any of these peptides. Real health decisions belong with a doctor who knows your full picture.
Most peptides aren't regulated like vitamins or supplements. Many are prescription-only drugs. Some are still being tested. Some are sold only for lab research. Treating them like a casual wellness purchase is a mistake.
Compounds sold "for research only" don't follow the same manufacturing standards as actual medications. Two vials with the same label can have very different actual contents. Quality, purity, and what's actually in there varies a lot between sources.
For a lot of these peptides, we don't yet know what years or decades of regular use does to a person. Animal studies and a few months of human trials can't tell us about long-term safety.
If something on this site interests you, the next step is a conversation with a doctor. Ideally one who knows hormones, metabolic medicine, or the specific peptide you're curious about. Not a forum. Not an influencer. Not a guy at the gym.
Every entry shows a last reviewed date. Regulatory status is checked against the FDA Bulk Drug Substances list, FDA approval letters and PCAC meeting minutes. Clinical claims should be reviewed by a named medical reviewer before broader release — this v1 is the editorial pass. If you find an error, please write us; corrections are logged with a date.