Peptides are short chains of amino acids — typically 2 to 50 — linked together by peptide bonds. They occur naturally in the body and play roles in cell signaling, immune function, and tissue repair; researchers study synthetic versions of many of them for these same processes. The notes below are general educational background, not a dosing recommendation. Need vial math? Try the free Reconstitution Calculator. Want per-compound regulatory status? Browse the free Research Library.
What are peptides?
Short chains of amino acids (typically 2–50) that act as signaling molecules for things like tissue repair, metabolism, and immune function.
Is this medical advice?
No. Everything on this page is for educational and research purposes only (RUO). Always consult a physician before making decisions about your health.
How do I use this page?
Expand a question below for a plain-English answer, or jump to a compound's full entry in the Research Library.
Foundational concepts and terms you'll see across this site. Tap a question to expand it.
What does "reconstitution" mean?
Many research peptides ship as a freeze-dried (lyophilized) powder in a sealed vial. Reconstitution is the process of adding a liquid — usually bacteriostatic water — to that powder to dissolve it into a liquid solution at a known concentration, so it can be measured and drawn accurately.
What is bacteriostatic (BAC) water, and why is it used?
Bacteriostatic water is sterile water with a small amount of benzyl alcohol added, which inhibits bacterial growth so a multi-use vial stays viable for longer once it's been opened, versus plain sterile water. It's the liquid most commonly used to reconstitute lyophilized peptides.
What's the difference between mg and mcg?
A milligram (mg) is 1,000 micrograms (mcg) — mcg is one-thousandth the size of a mg. Vial sizes are almost always labeled in mg, while individual dose amounts are often discussed in mcg, so keeping the two straight (and double-checking your decimal point) matters a lot in this math.
What does "concentration" mean once a vial is mixed?
Concentration is how much peptide is present per unit of liquid after reconstitution — usually expressed as mg/mL or mcg/mL. It's calculated as the total peptide in the vial divided by however much liquid you added, and it's the number that turns a target dose into an actual draw volume.
What is a "blend," and how is dosing different?
A blend is two or more compounds combined into a single vial (for example, a BPC-157/TB-500 blend). Because more than one compound shares the same liquid, the concentration of each individual compound is lower than if it were reconstituted alone — the math needs to account for each compound's share of the total mg in the vial.
What does "half-life" mean?
Half-life is the time it takes for half of a substance to be cleared from the body. It's a general pharmacological concept researchers use to think about how often a compound might need to be dosed to maintain a given effect — it varies by compound and isn't the same thing as how long an effect "lasts."
What does RUO ("Research Use Only") mean?
RUO is a labeling designation meaning a substance is sold and intended strictly for laboratory research — not for human or animal consumption, and not evaluated by regulators for that use. Most of the compounds discussed on this site are sold under RUO labeling.
What's the difference between "FDA-approved," "investigational," and "unapproved" in the Research Library?
FDA-approved means the compound has an approved drug application for a specific labeled use (often a narrow one — approval for one use doesn't cover other uses). Investigational means it's currently in the clinical-trial process and not yet approved. Unapproved means it has no FDA-approved drug application at all. Regulatory status can change, so always verify current status directly with the FDA or a licensed pharmacist.
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Click a compound below for its full regulatory-status entry, or browse the complete library.