What's the difference between mcg and mg?

1 milligram (mg) = 1,000 micrograms (mcg). Peptide vials are sold in mg (e.g., 5mg, 10mg), but individual doses are usually measured in mcg (e.g., 250mcg, 500mcg). Use our unit converter tool for quick conversions.

What's the difference between BAC water and sterile water?

BAC water contains 0.9% benzyl alcohol as a preservative, allowing multi-use over weeks. Sterile water has no preservative and must be used within 24 hours of reconstitution. Always use BAC water for peptides.

What does "half-life" mean for dosing?

Half-life determines how often you need to dose. A peptide with a 2-hour half-life needs daily or twice-daily dosing, while one with a 7-day half-life (like Semaglutide) only needs weekly dosing.

Peptide Glossary

Common peptide terms explained — from BAC water to subcutaneous injection, reconstitution to half-life.

A-B

Amino Acid — The building blocks of peptides and proteins. There are 20 standard amino acids. BAC Water (Bacteriostatic Water) — Sterile water with 0.9% benzyl alcohol added as a preservative. Used to reconstitute peptides for multi-use vials. Bioavailability — The percentage of a substance that reaches systemic circulation after administration. SubQ bioavailability varies by peptide. BPC — Body Protection Compound. Refers to BPC-157, a 15-amino acid healing peptide.

C-D

Concentration — The amount of peptide per unit volume after reconstitution, expressed as mcg/mL. Cycling — Alternating between on and off periods to prevent receptor desensitization. DAC (Drug Affinity Complex) — A modification added to CJC-1295 that allows it to bind to albumin, extending its half-life from 30 minutes to ~8 days. Dose — The amount of peptide administered per injection, typically measured in mcg (micrograms).

G-I

GHRH (Growth Hormone Releasing Hormone) — A hormone that stimulates the pituitary to release growth hormone. CJC-1295 is a GHRH analog. GHRP (Growth Hormone Releasing Peptide) — Peptides that trigger GH release by binding to the ghrelin receptor. Includes Ipamorelin, GHRP-2, GHRP-6. GLP-1 (Glucagon-Like Peptide-1) — An incretin hormone that regulates appetite and blood sugar. Semaglutide and Tirzepatide are GLP-1 agonists. Half-life — The time it takes for half the peptide to be eliminated from your body. Determines dosing frequency. IU (International Unit) — A unit of measurement for biological substances like HGH. 1mg HGH ≈ 3 IU.

L-R

Loading Phase — An initial period of higher or more frequent dosing to reach therapeutic levels quickly (common with TB-500). Lyophilized — Freeze-dried. The powder form peptides are shipped in for maximum stability. mcg (Microgram) — One millionth of a gram. Most peptide doses are measured in mcg. 1mg = 1,000mcg. Reconstitution — The process of dissolving lyophilized peptide powder in BAC water to create an injectable solution.

S-U

Secretagogue — A substance that stimulates the secretion of a hormone. MK-677 is a GH secretagogue. SubQ (Subcutaneous) — Injection into the fat layer beneath the skin. The most common peptide injection route. Syringe Units — Markings on an insulin syringe. On a U-100 syringe, 100 units = 1mL. Titration — Gradually increasing dose over time to find the optimal level and minimize side effects. Critical for GLP-1 agonists. Units — On insulin syringes, units are the markings used to measure volume. The number of units per mL depends on the syringe type (U-100 = 100 units/mL).

Frequently Asked Questions

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