Dosage guide · 5 mg vial

LL-37 Dosage Protocol

Human cathelicidin antimicrobial peptide · CAP-18

The reference protocol lists one subcutaneous administration daily: 50 mcg in week 1, rising by 50 mcg each week to 400 mcg in week 8. With 3 mL of bacteriostatic water, a 5 mg vial is 1.67 mg/mL, so the 50 mcg start is 3 units (0.03 mL) on a U-100 syringe. These are community-reported, not clinically established subcutaneous amounts.

How oftenOnce daily

Starting dose50 mcg

Start = units3 units

Mix3 mL BAC water

Reviewed 25 Oct 2026 · Education only, not medical advice

LL-37 5 mg vial

Not currently stocked by Peak Peptides Australia

No product photo — this strength isn't stocked by Peak

Dosage chart How to mix Supplies Calculator About LL-37 References

01 · DOSAGE CHART

LL-37 dosage chart

Weekly gradual approach · 5 mg vial + 3 mL BAC water

BAC water added

Concentration1.67 mg/mL

1 unit (U-100)16.7 mcg= 0.01 mL

How oftenOnce dailySubcutaneous injection

3 mL is the mix used by the attributed 5 mg reference protocol, giving 1.67 mg/mL and 3 units for 50 mcg.

LL-37 dosage chart for a 5 mg vial mixed with 3 mL of bacteriostatic water
Week	Daily dose	Syringe units
Week 1Start	50 mcg	3 units0.03 mL
Week 2	100 mcg	6 units0.06 mL
Week 3	150 mcg	9 units0.09 mL
Week 4	200 mcg	12 units0.12 mL
Week 5	250 mcg	15 units0.15 mL
Week 6	300 mcg	18 units0.18 mL
Week 7	350 mcg	21 units0.21 mL
Week 8Max	400 mcg	24 units0.24 mL

Once daily · any consistent time · subcutaneous injection

The attributed protocol increases by 50 mcg each week through week 8.

It describes 8–12 week cycles and optional extension to 16 weeks, but does not state a separate post-week-8 daily amount.

The chart is a reference-site educational schedule, not a clinically established subcutaneous regimen.

Community-reported subcutaneous amounts — LL-37 has no approved or clinically established subcutaneous human dose. Education only, not medical advice. Dose amounts adapted from LL-37 5 mg vial dosage protocol (PeptideDosages.com); units are recalculated for the vial and mix selected above.

02 · HOW TO MIX

Mixing a 5 mg vial with 3 mL of BAC water

Using a 1 mL (100-unit) insulin syringe, 3 full draws of bacteriostatic water gives 1.67 mg/mL.

1
Add the water slowly
Wipe both rubber stoppers with an alcohol swab and let them dry. Draw 3 mL of bacteriostatic water and let it run slowly down the inside of the vial wall — not straight onto the powder.
2
Swirl gently
Swirl or roll the vial gently until the powder has dissolved. Give it a few minutes to settle if needed.
3
Don't shake it
Shaking can damage the peptide and cause foaming. Gentle swirling only.
4
Check it's fully clear
Only use it once it is fully clear with no particles. Label the vial with the date and 1.67 mg/mL, then store it in the fridge at 2–8 °C.

Full illustrated reconstitution guide

03 · SUPPLIES NEEDED

What you'll need

Counts follow the dosage chart above at the highest amount in each step, using a 5 mg vial mixed with 3 mL.

Length of protocol

3LL-37 5 mg vials12.6 mg needed in total

591 mL insulin syringesU-100, 27–31G · one per draw + one per vial mixed

1BAC water 10 mL bottle9 mL used for mixing

118Alcohol swabsSkin + stopper, every time

Plus an approved sharps container. Syringes and swabs are sold by Australian pharmacies — Peak Peptides and Pure Performance supply the bacteriostatic water.

Peak Peptides Australia Bacteriostatic water 10 mL

Bacteriostatic water 10 mLPeak Peptides Australia

Pure Performance Australia Bacteriostatic water 10 mL

Bacteriostatic water 10 mLPure Performance Australia

04 · CALCULATOR

Check a different amount

Enter your vial, water and dose to see the matching syringe units.

Concentration Calculator

Labelled Vial Amount (mg)

Verified Final Liquid Volume3 mL

Amount to Evaluate (not a recommendation)

mcg

Concentration

1.67 mg/mL

(1667 mcg/mL)

Calculated Liquid Volume

0.030 mL

Equivalent U-100 volume scale position

3markings (not biological IU)

Illustration of a U-100 volume scale, not preparation or injection guidance

05 · PROTOCOL DETAILS

About LL-37

Protocol overview

Starting dose: 50 mcg once daily in week 1
How it increases: Add 50 mcg each week to 400 mcg in week 8
Frequency: Once daily
When to take it: Any consistent time of day
Cycle length: Reference page: 8–12 weeks, with optional extension to 16
Common mix: 3 mL bacteriostatic water gives 1.67 mg/mL

Storage

Before mixing: The attributed protocol says to keep lyophilised material at −20 °C in dry, dark conditions; follow the exact vial label.
After mixing: Refrigerate at 2–8 °C and protect from light; do not assume a beyond-use date without stability data for the exact product.
Never: Do not use a mixed vial that is cloudy or has particles, and avoid repeated freeze–thaw cycles.

How it works

LL-37 is the 37-amino-acid active fragment of the human cathelicidin precursor hCAP18. It is part of innate immune defence and is produced after protease cleavage in cells such as keratinocytes and neutrophils.

In laboratory systems, its positive charge favours binding to negatively charged microbial membranes; its alpha-helical structure can then disrupt those membranes. It also has context-dependent immune-signalling effects, so antimicrobial laboratory findings do not establish a clinical benefit from subcutaneous use.

Illustrated mechanism explainer

What the research shows

In a 2014 randomised topical venous-leg-ulcer trial, 34 participants received twice-weekly local LL-37 at 0.5, 1.6 or 3.2 mg/mL for 4 weeks. Mean ulcer-area reduction was 68% in the 0.5 mg/mL group and 50% in the 1.6 mg/mL group; the study reported no local or systemic safety concerns.
A 2021 multicentre venous-leg-ulcer trial enrolled 149 participants and tested twice-weekly local 0.5 or 1.6 mg/mL LL-37 for 13 weeks with compression therapy. Its conclusion concerned local application, not subcutaneous dosing.
A completed melanoma investigation enrolled 4 participants for intratumoural LL-37, beginning at 250 mcg per tumour weekly for up to 8 weeks. It was an investigational local-treatment setting, not evidence for daily subcutaneous administration.
The ARTG search returned no LL-37 result, and the melanoma trial record states LL37 is not FDA approved or commercially available. LL-37 is not an approved medicine in Australia or the United States on the sources checked.

Reported side effects

The 34-participant venous-ulcer trial reported no local or systemic safety concerns during 4 weeks of topical treatment; that result does not establish safety of a reconstituted subcutaneous product.
Human safety information for repeated daily subcutaneous use is not established. Published human work reviewed here used local topical applications or intratumoural injections instead.
LL-37 has context-dependent immune and inflammatory actions. Laboratory evidence indicates that at higher concentrations it can penetrate mammalian membranes, but the relevance to subcutaneous exposure in people is unknown.

Important notes

ARTG search returned no LL-37 entry. It is not an approved medicine in Australia, and the retrieved clinical-trial record states it is not FDA approved.
Prohibited in sport while unapproved: the current WADA S0 category prohibits pharmacological substances without current approval by any governmental health authority. LL-37 is not named individually in the retrieved list.
The human studies opened used topical or intratumoural LL-37. This reference-site subcutaneous schedule is not evidence of treatment for infection, wounds, cancer or any other condition.
No Peak or Pure product page was supplied for this item, so product-specific identity, sterility, potency and stability cannot be verified here.
Never use a mixed vial that is cloudy or has particles in it.

Injection basics

Use a new sterile 1 mL (100-unit) U-100 insulin syringe, 27–31G, every time — never reuse or share.
Wipe the vial stopper and the skin with an alcohol swab and let both dry first.
Inject under the skin (subcutaneously) of the abdomen, thigh or upper arm, and rotate sites.
Put used syringes straight into an approved sharps container — the NDSS lists Australian disposal options.

Guidance: World Health Organization · National Diabetes Services Scheme (NDSS)

06 · QUICK ANSWERS

LL-37 questions

How many units is 50 mcg of LL-37 in a 5 mg vial?

With 3 mL in a 5 mg vial, the concentration is 1.67 mg/mL. A 50 mcg amount is 3 units, or 0.03 mL, on a U-100 syringe.

How many units is 400 mcg of LL-37 in a 5 mg vial?

With the default 3 mL mix, 400 mcg is 24 units, or 0.24 mL, on a U-100 syringe.

How much bacteriostatic water is used for a 5 mg LL-37 vial?

The attributed 5 mg reference protocol uses 3 mL. That calculation gives 1.67 mg/mL, and 30 U-100 units contains 0.5 mg.

How long does a 5 mg LL-37 vial last?

By arithmetic, a 5 mg vial contains 100 amounts of 50 mcg or 12.5 amounts of 400 mcg. The published reference chart gives an eight-week step-up sequence rather than a validated product use-by period.

07 · SOURCES