GHK-Cu vs LL-37
Overview
GHK-Cu is primarily a healing & recovery peptide, while LL-37 is used for immune support.
This page compares GHK-Cu and LL-37 across their primary use, typical dosing, reported benefits and side effects, and U.S. regulatory status. For the full monograph on either compound — mechanism of action, clinical research, and references — follow the article links.
Side-by-side comparison
| GHK-Cu | LL-37 | |
|---|---|---|
| Category | Healing & Recovery | Immune Support |
| Regulatory status (US) | Compounding (Rx) — Apr 2026 | Compounding (Rx) — Apr 2026 |
| Typical dosage | 1-3 mg | 2-5 mg |
| Frequency | daily | twice weekly |
| Reported benefits | Wound healing, collagen synthesis, anti-inflammatory, antioxidant effects, tissue remodeling | Antimicrobial activity, immune modulation, wound healing, anti-inflammatory |
| Reported side effects | Generally safe. Possible: mild skin irritation with topical use | Generally safe, minimal side effects |
Key differences
Primary use. GHK-Cu is categorised under Healing & Recovery, while LL-37 falls under Immune Support. Their differing categories mean they are usually chosen for different goals rather than as direct substitutes.
Regulatory status. GHK-Cu: not FDA-approved; compounding permitted with a prescription as of April 2026. LL-37: not FDA-approved; compounding permitted with a prescription as of April 2026.
Dosing. GHK-Cu is typically dosed at 1-3 mg (daily). LL-37 is typically dosed at 2-5 mg (twice weekly).
Can you stack them?
Some protocols combine peptides, but stacking GHK-Cu and LL-37 has not been validated for safety or efficacy in controlled trials. Combining compounds can change their effects and risks. Nothing here is medical advice — consult a qualified healthcare provider before starting or combining any protocol.
Frequently asked questions
- What is the difference between GHK-Cu and LL-37?
- GHK-Cu is primarily a healing & recovery peptide, while LL-37 is used for immune support. GHK-Cu is not FDA-approved; compounding permitted with a prescription (as of April 2026), whereas LL-37 is not FDA-approved; compounding permitted with a prescription (as of April 2026).
- What is GHK-Cu used for?
- Wound healing, skin regeneration.
- What is LL-37 used for?
- Antimicrobial defense peptide.
- Can you take GHK-Cu and LL-37 together?
- Some users combine peptides within a single protocol, but stacking GHK-Cu and LL-37 has not been established as safe or effective in controlled trials. Neither this comparison nor PeptideSciences101 is medical advice — consult a qualified healthcare provider before combining any compounds.
- Is GHK-Cu or LL-37 FDA-approved?
- GHK-Cu is not FDA-approved; compounding permitted with a prescription (as of April 2026). LL-37 is not FDA-approved; compounding permitted with a prescription (as of April 2026).