Reconstituting peptides – how much bac water for a 5mg vial?

Posted by fasted_scientist in Beginner Questions - 9 points, 3 comments.

Hey folks, I’m totally new to this and I’m stuck on the maths for mixing. I got a 5mg vial of something and the guide says to add bac water until you reach a certain concentration, but I’m not sure how to work out the volume. I tried adding 1ml and then calculating, but the numbers feel off and I don’t want to mess up the dose.

For me it’s just guesswork at the moment and I’d rather get it right before I pin anything. Could someone walk me through the steps in plain English? Like, if I want 250mcg per shot, how much water do I need and how do I draw it out?

I’ve read a few threads but they jump straight to the answer without showing the workings. Any beginner‑friendly breakdown would be really helpful. Thanks in advance.

Comments

• tracker_jade: I’ve been there – the math feels weird at first. For a 5 mg vial, 5 mg equals 5000 mcg. If you want 250 mcg per shot you’ll need 20 shots total (5000 ÷ 250 = 20). Pick a total volume that’s easy to measure, like 2 ml of bac water. That gives you 2500 mcg per ml (5000 mcg ÷ 2 ml). 1). 05 ml per dose. Just double‑check your syringe markings before you pin.
• fasted_scientist: Ngl that’s spot on – I usually go with 2 ml bac water for a 5 mg vial so each 0.1 ml gives me 250 mcg. Much easier to read on an insulin syringe than trying to hit 0.05 ml. Works fine for me.
• fasted_scientist: Ngl that’s spot on. I usually go with 2ml water for a 5mg vial too – makes the maths easy and 0.1ml per 250mcg shot lines up nicely on an insulin syringe. Just check the syringe’s scale before you pin.

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