PeptideCalculations
37-amino-acid peptide · 5 mg vials

LL-37 calculator

LL-37 is the active fragment of human cathelicidin, an antimicrobial peptide your own cells make. The only human trial is topical: 0.5 to 1.6 mg/mL applied twice a week to leg ulcers sped healing, and 3.2 mg/mL did not.

mL
Draw to
—units
— mL on a U-100, 1 mL barrel
Concentration
—mg/mL
— mcg per unit
Doses in the vial
—
of
LL-37 dosage
0.5 mg/mL to 1.6 mg/mL topical, twice weeklyper application · clinical trial (Gronberg et al. 2014, Wound Repair Regen, 34 patients with venous leg ulcers, randomized, placebo-controlled, 4 weeks)
Frequency
once daily, 5 days a week (community); twice weekly topical (trial)
Timing
any time; near a wound site for local use
Cycle
2 to 4 weeks on, 2 weeks off
Route
subcutaneous (community) or topical on wounds (trial)
Easy mix
5 mg + 5 mL = 1 mg/mL, so 100 mcg = 0.1 mL = 10 units and 200 mcg = 20 units. For a topical mix in the trial range, 5 mg in 5 mL is already 1 mg/mL.

Full LL-37 dosage chart →

LL-37 units chart

5 mg vial. Rows are doses; columns show the units to draw on a U-100 syringe at each water volume.

5 mg vial + 5 mL = 1 mg/mL (1,000 mcg/mL, 10 mcg per unit on U-100)
DosemLU-100 unitsDoses per vial
100 mcg0.11050
200 mcg0.22025
250 mcg0.252520
500 mcg0.55010
1 mg11005
2 mg22002
2.5 mg2.52502
5 mg55001

Other mixes: 5 mg + 1 mL · 5 mg + 2 mL · 5 mg + 3 mL

About the LL-37 math

LL-37 is a 37-amino-acid fragment of human cathelicidin. A smaller set of suppliers carries it, and the listing is almost always a 5 mg vial of lyophilized powder. The example draw here is 200 mcg, run at three solvent volumes. A 5 mg vial with 2 mL of bacteriostatic water is 2.5 mg/mL, or 2,500 mcg/mL. A 200 mcg draw is 0.08 mL, or 8 units on a U-100 syringe, and 5,000 divided by 200 is 25 draws per vial. With 2.5 mL the concentration is 2,000 mcg/mL and the same draw is 0.1 mL, or an even 10 units. With 1 mL it is 5,000 mcg/mL and 200 mcg shrinks to 0.04 mL, or 4 units. A 100 mcg draw halves each of those figures: 4 units, 5 units and 2 units, with 50 draws in the vial. For a draw this small, the 2.5 mL fill is the one that puts a round 100 mcg on every 5 units, which is the easiest spacing to read on a 0.3 mL or 0.5 mL barrel.

LL-37 questions

LL-37 peptide dosage?

No human injection dose exists. Community use is 100 to 200 mcg subcutaneously once a day, 5 days a week, for 2 to 4 weeks. The human trial used it on the skin at 0.5 to 1.6 mg/mL twice a week, and the higher 3.2 mg/mL dose did worse than the low ones.

How many units of LL-37 is 100 mcg?

With 5 mg in 5 mL (1 mg/mL) 100 mcg is 10 units. With 2 mL of water it is 4 units, which is hard to read, so use the full 5 mL.

How many units is 200 mcg of LL-37 at 5 mg in 2 mL?

5 mg divided by 2 mL is 2.5 mg/mL, or 2,500 mcg/mL. 200 mcg divided by 2,500 mcg/mL is 0.08 mL. On a U-100 syringe 0.08 mL is 8 units.

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

Any volume the vial holds. 1 mL gives 5 mg/mL, 2 mL gives 2.5 mg/mL and 3 mL gives 1.67 mg/mL (rounded). A 100 mcg draw is 2 units, 4 units or 6 units at those three concentrations.

How many 100 mcg draws are in a 5 mg vial of LL-37?

5 mg is 5,000 mcg, and 5,000 divided by 100 is 50 draws. The count does not depend on solvent volume; with 2.5 mL in the vial each 100 mcg draw is 0.05 mL, or 5 units.

Brands we recommend for LL-37. We are independent and have no affiliation with any brand: no affiliate links, no referral codes, no paid placements. These are the suppliers whose testing and certificates hold up when we check them.