Beginner's Guide to Peptides

Peptides are short chains of amino acids — the same building blocks that make up proteins, just smaller. The human body uses peptides as signaling molecules to regulate growth, repair, metabolism, inflammation, and many other processes.

In research, peptides are studied for their highly specific effects: a given peptide typically targets a single receptor or pathway. Most are sold as a freeze-dried (lyophilized) white powder in a small glass vial and must be mixed with sterile water before use.

Before you reconstitute anything, gather the full kit. Trying to improvise mid-process is how vials get contaminated.

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Concentration is the single most important number in peptide dosing. It is simply how much peptide is dissolved in each milliliter of solution:

Example: a 5 mg vial mixed with 2 mL of BAC water gives a concentration of 2.5 mg/mL (or 2,500 mcg/mL). The amount of peptide in the vial does not change — only how concentrated the solution is.

More BAC water = larger draw volume per dose (easier to measure small doses). Less BAC water = smaller draw volume (better when doses are large).

1. Wash hands. Lay out a clean surface and all supplies.
2. Wipe both vial stoppers (peptide + BAC water) with an alcohol swab. Let dry.
3. Draw the planned volume of BAC water into a mixing syringe (e.g. 2 mL for a 5 mg vial at 2.5 mg/mL).
4. Insert the needle into the peptide vial at a 45° angle. Push the plunger slowly so water runs down the inside wall of the vial, not directly onto the powder.
5. Withdraw the empty syringe. Do not shake.
6. Gently swirl or roll the vial between your palms until the powder fully dissolves. The solution should be clear.
7. Label the vial with the date, peptide, and concentration. Refrigerate.

Most research peptides are administered subcutaneously (SubQ) — into the fatty layer just under the skin — using a short insulin syringe. A few are intramuscular (IM) or intranasal.

• Subcutaneous: 5/16" or 1/2" insulin needle, 90° into a pinched fold of skin/fat on the abdomen, flank, or thigh.
• Intramuscular: longer needle (1") into the deltoid, vastus lateralis (thigh), or glute. Used only for specific peptides.
• Intranasal: measured dropper or atomizer into the nostril, head tilted back. Used for Semax, Selank, etc.

Rotate injection sites to avoid bruising, scar tissue, and lipohypertrophy (lumpy fat deposits that absorb erratically). A simple rotation: alternate left/right and move at least 1" from the previous spot each day. The dose log in this app tracks rotation for you.

• Lyophilized (unmixed): long-term storage in the freezer (-20 °C); stable for months to years depending on the peptide.
• Reconstituted: refrigerated (2–8 °C). Most peptides remain potent for 2–4 weeks; some (GHK-Cu, BPC-157) up to 30 days. Light-sensitive peptides like NAD+ and glutathione should be wrapped in foil.
• Never freeze a reconstituted vial — ice crystals damage the peptide chain.
• Discard if solution turns cloudy, yellow/brown, or develops particulates.

A typical protocol line looks like:

• Dose: 250 mcg = 0.25 mg per injection
• Route: SubQ (subcutaneous)
• Frequency: once or twice per day
• Cycle: 4–6 weeks of use, then a 2-week break

Use the peptide library to look up the cycle, route, and dose range for each peptide, then the calculator on the peptide page to convert mcg → syringe units.

• Shaking the vial instead of swirling — denatures the peptide.
• Spraying BAC water directly onto the powder — same problem.
• Reusing needles — instant contamination and dulling causes painful injections.
• Not labeling the vial — you will forget the concentration in 48 hours.
• Mixing mcg and mg in the math — always convert before calculating units.
• Storing reconstituted vials at room temperature.
• Injecting into the same spot repeatedly.

mcg

Microgram. 1 mg = 1,000 mcg.

mg

Milligram. The most common vial size unit.

IU

International Unit. A standardized measure used for HGH and some hormones.

Units

On an insulin syringe, 100 units = 1 mL (U-100 scale).

SubQ

Subcutaneous — under the skin, into fat.

IM

Intramuscular — into muscle tissue.

BAC water

Bacteriostatic water, sterile water with 0.9% benzyl alcohol.

Half-life

Time for half the peptide to clear the body. Drives dosing frequency.

Lyophilized

Freeze-dried. The powder form most peptides ship as.

Reconstitution

Mixing BAC water into the powder to create an injectable solution.