LL-37 is a cathelicidin peptide. Thymulin is a thymic peptide.
They are aimed at different things: LL-37 at antimicrobial & healing; Thymulin at immune & inflammation.
| Comparison | LL-37 cathelicidin · hCAP-18 | Thymulin serum thymic factor · FTS |
|---|---|---|
| How it works | How it works LL-37 is part of your innate immune system, the fast general-purpose defence that acts before your body has identified what it is fighting. | How it works Thymulin only works when bound to zinc. Without it the molecule is inactive, which makes it unusual and makes zinc status directly relevant. |
| What it is | A natural germ-fighting peptide for stubborn infections and wound healing. | A thymus peptide studied for immune balance and calming inflammation. |
| Status | Research only | Research only |
| Typical dose | 0.1–0.5 mg per dose | 1 mg per dose |
| How often | Daily, short courses | Daily/weekly |
| Stays active | Nothing published | Nothing published |
| Dose comes from | Community practice | Community practice |
| Cycled? | Taken in daily, short courses Community practice | No established schedule No established range |
| What it does | ||
| Drug class | Cathelicidin peptide | Thymic peptide |
| Used for | A natural germ-fighting peptide used against stubborn infections, biofilms, and gut bugs, and to support wound healing. | A thymus peptide studied for balancing immune function and calming inflammation and pain. |
| Receptors hit | — | — |
| Numbers | ||
| Full dose line | 0.1 up to 0.5 mg per dose (start low, increase slowly) | 1 mg per dose |
| Why that cycle | Course dosing is how this one is normally used. Where the course length comes from is the thing to check: for most compounds in this pattern it is convention rather than a tested schedule. | No published study has established how long to take this or whether a break is needed. Schedules quoted online come from vendors and forums, and different sources disagree. |
| Weight / effect | Not measured in a trial | Not measured in a trial |
| Chain length | 37 residues | 9 residues |
| Common vial | 5 mg | 10 mg |
| Before you start | ||
| Route | Under the skin (subcutaneous) | Under the skin (subcutaneous) |
| Do not use if | No established systemic safety profile Pregnancy Autoimmune conditions, as a theoretical precaution | No controlled human safety trials exist Pregnancy |
What separates them
Proof behind the dose. Every dose here comes from community practice. Not one is backed by a published human study, which is worth knowing before you read the numbers as if they were equivalent.
What doesn't differ: They are both taken the same way (under the skin). Neither has a measured effect size from a published trial, so there is no number to rank them on.
What people actually report
LL-37
- It can irritate the injection site, with a theoretical autoimmune concern, and there is little human data.
- Signs of an allergic reaction
- A spreading rash or worsening inflammation
Thymulin
- Little human evidence.
- Signs of an allergic reaction
- Anything unusual, given the absence of human data
Side effects are what users and trials report most often, not a complete list. Anything sudden, spreading, or breathing-related is an emergency regardless of which compound caused it.
People also compare
This comparison does not cover cost, long-term safety, or how you personally will respond. Effect figures come from separate trials in different populations and are not always directly comparable to each other. Nothing here is medical advice or a recommendation to use any of these. Talk to a clinician about your own situation.