LL-37 vs Splenopentin
Overview
LL-37 and Splenopentin are both immune support peptides, but they differ in mechanism, dosing, and regulatory status.
This page compares LL-37 and Splenopentin 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
| LL-37 | Splenopentin | |
|---|---|---|
| Category | Immune Support | Immune Support |
| Regulatory status (US) | Compounding (Rx) — Apr 2026 | Research use only |
| Typical dosage | 2-5 mg | 1-5 mg |
| Frequency | twice weekly | as needed |
| Reported benefits | Antimicrobial activity, immune modulation, wound healing, anti-inflammatory | Immune modulation, anti-inflammatory, autoimmune support |
| Reported side effects | Generally safe, minimal side effects | Well-tolerated |
Key differences
Primary use. LL-37 is categorised under Immune Support, while Splenopentin falls under Immune Support. Because they target a similar goal, they are common alternatives to weigh against each other.
Regulatory status. LL-37: not FDA-approved; compounding permitted with a prescription as of April 2026. Splenopentin: not FDA-approved; treated as a research compound.
Dosing. LL-37 is typically dosed at 2-5 mg (twice weekly). Splenopentin is typically dosed at 1-5 mg (as needed).
Can you stack them?
Some protocols combine peptides, but stacking LL-37 and Splenopentin 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 LL-37 and Splenopentin?
- LL-37 and Splenopentin are both immune support peptides, but they differ in mechanism, dosing, and regulatory status. LL-37 is not FDA-approved; compounding permitted with a prescription (as of April 2026), whereas Splenopentin is not FDA-approved; generally classified as a research compound.
- What is LL-37 used for?
- Antimicrobial defense peptide.
- What is Splenopentin used for?
- Spleen-derived immune peptide.
- Can you take LL-37 and Splenopentin together?
- Some users combine peptides within a single protocol, but stacking LL-37 and Splenopentin 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 LL-37 or Splenopentin FDA-approved?
- LL-37 is not FDA-approved; compounding permitted with a prescription (as of April 2026). Splenopentin is not FDA-approved; generally classified as a research compound.
Read the full articles
- LL-37 — full monograph: mechanism, research, dosing & references
- Splenopentin — full monograph: mechanism, research, dosing & references