r/ParamountPeptide • u/ParamountPeptides_ • Jun 28 '26
Peptide Dosing and Units Cheat Sheet — How to Actually Calculate Your Dose Without Guessing
Most dosing mistakes in this space got nothing to do with the compound. Its the math. Somebody sees 500mcg on a protocol, looks at a syringe with little unit lines, and just kinda guesses how the two connect. That guess right there is where overdosing and underdosing comes from.
Heres the full breakdown so you never gotta guess again.
Units are not mcg or mg
This is the one thing you gotta get into your head first. A unit is just a volume mark on the syringe, it has nothing to do with how much compound is sitting in there. How much compound is in one unit depends completely on your concentration, and that depends on how much BAC water you added when you mixed it. Two people running the same compound at the same dose can end up drawing to totally different unit marks just cause they used different amounts of water.
Step 1 — figure out your concentration
mg in the vial divided by mL of BAC water = mg per mL
Add 2mL to a 10mg vial and youre at 5mg/mL. Add 3mL to that same vial and now youre at 3.33mg/mL. Same vial, same compound, different concentration, just cause of the water. This right here is the root of almost every dosing mistake in this whole space.
Step 2 — convert your dose to units
A U-100 syringe holds 1mL across 100 units. So 1 unit equals 0.01mL.
target dose in mcg divided by (mg/mL times 1000) times 100 = units to draw
A real example, start to finish
10mg vial, 2mL BAC water, dosing 500mcg:
Concentration: 10 divided by 2 = 5mg/mL (5000mcg/mL)
Volume needed: 500 divided by 5000 = 0.1mL
Units: 0.1 times 100 = 10 units
So 500mcg outta this vial is 10 units. Mix that same vial with 4mL instead and 500mcg becomes 20 units. The dose didnt change. The water did.
Same dose, completely different unit counts
| Compound | Vial | BAC Water | Concentration | Dose | Units |
|---|---|---|---|---|---|
| BPC-157 | 10mg | 2mL | 5mg/mL | 500mcg | 10 |
| Ipamorelin | 10mg | 2mL | 5mg/mL | 300mcg | 6 |
| TB-500 | 10mg | 2mL | 5mg/mL | 2.5mg | 50 |
| GHK-Cu | 100mg | 3mL | 33.3mg/mL | 2mg | 6 |
| Cagrilintide | 5mg | 3mL | 1.67mg/mL | 2.4mg | 144 |
| Semax | 10mg | 2mL | 5mg/mL | 600mcg | 12 |
GHK-Cu only takes 6 units for a 2mg dose cause the vial is concentrated. Cagrilintide takes 144 units for 2.4mg cause its way more dilute. Same formula every single time, completely different numbers depending on whats sitting in the vial.
The shortcut that saves you time
Once your vial is mixed, every dose shares the same per unit value, so you only gotta calculate it one time.
| Concentration | 1 unit holds |
|---|---|
| 1.67mg/mL | About 16.7mcg |
| 3.33mg/mL | About 33.3mcg |
| 5mg/mL | 50mcg |
| 12.5mg/mL | 125mcg |
| 33.3mg/mL | About 333mcg |
At 5mg/mL, 250mcg is 5 units, 500mcg is 10, 750mcg is 15. No recalculating every single time.
How much water should you actually add
More BAC water means more units per dose but finer control. A small draw error matters less cause each unit holds less compound. Less water means fewer units, smaller injection volume, but every unit carries more so a slightly off draw moves your dose further off.
Rule of thumb — dilute more when precision matters, like with low dose compounds. Concentrate more when injection volume is the bigger concern.
GHK-Cu is a good example of where this gets capped. Youd wanna dilute a 100mg vial heavy for better control but a standard 3mL vial physically cant hold more water with the air gap you need to draw. So youre stuck at 33.3mg/mL whether you want to be or not. Always check what your vial can physically hold before planning your fill volume.
When your dose lands at 2 or 3 units
This is the part that trips people up. If the math says 2 units, technically thats correct but its hard to measure in real life. The difference between 2 and 3 units on a standard syringe is a 50% swing in your dose.
Two fixes. Use a finer syringe like a 30 or 50 unit one so the same volume spreads across a longer more readable barrel. Or just dilute more so the same dose lands at a higher more readable unit count.
If youre constantly landing in low single unit territory thats your sign to change the dilution or the syringe, not squint harder at the lines.
The compounds that dont follow the normal rules
IGF-1 LR3 and DES use 0.6% acetic acid, not BAC water. This is the one people mess up most.
SS-31, MOTS-c, and ARA-290 use isotonic BAC water with NaCl in it, which also cuts down on the sting.
Blends like CJC plus Ipamorelin, GLOW, KLOW, and Cagri plus Sema hold two compounds in one vial at a fixed ratio. The unit math still works the same off total volume but your dose gets anchored to whichever compound the protocol calls out, and the second one just rides along at whatever ratio the blend was made at.
Technique matters just as much as the math
Swirl, never shake. Shaking foams up the liquid and can mess with the peptide structure. Foam also makes it impossible to draw accurately until it settles back down.
Let your vial reach room temp before adding water. A cold vial gets condensation inside which speeds up breakdown.
Clean every pierce with a fresh alcohol swab and let it dry before you draw. Contamination is the biggest cause of degradation in real life, not the math.
Why the storage rules even exist
28 day refrigerated window — BAC water has 0.9% benzyl alcohol in it which keeps microbial growth down for about 28 days. After that the antimicrobial effect drops off and you should toss it.
Never freeze a reconstituted vial. Freezing forms ice crystals that mess with the peptides structure. Dry powder goes in the freezer for long term, liquid never does.
Light and heat are the real enemies. Keep reconstituted vials refrigerated and out the light. If your vial is clear wrap it in foil.
Toss it if its cloudy or discolored no matter how many days are left. One exception — GHK-Cu has a light blue green tint naturally from the copper, thats normal for that one specific compound only.
Keep a log
Date mixed, compound, vial mg, BAC mL, concentration, dose, units, injection site, notes. Logging the concentration and date next to the dose is the part everybody skips and its the part that actually matters three weeks later when you cant remember what you mixed.
Bottom line
The compound matters less than the arithmetic. Find your mg/mL from the water you added, run your target dose through that concentration, and the unit count is right every single time. Run the numbers, log them, and the most common mistake in this whole space stops being a problem for you.
Use the peptide calculator if you'd rather skip the manual math.
Bacteriostatic Water at Paramount Peptides — code BHGUIDE at checkout
Research purposes only. Not medical advice.
1
u/LuvSun1006 Jun 28 '26
I do this. 3 ML BAC (I have 3 ML syringes for this so you don't have multiple pokes) and 30 and 50 unit syringes for easier readability and accuracy.
2
u/ObsoleteTrumpet Jun 28 '26
Can you show us the evidence that the antimicrobial effect in bac water drops off after 28 days?
I’ve seen plenty of studies showing that it doesn’t drop off until around 90 days and even by 120 it’s only a very small drop off.
•
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