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Reconstituting a 10mg vial, bac maths confused me, can someone walk me through it?

Posted by fasted_scientist in Beginner Questions - 1 points, 4 comments.

Right so I got my first vial in the post today, 10mg of BPC-157, and I'm staring at the bac water trying to figure out how much to draw up. The vial came with no clear instructions beyond "reconstitute with bacteriostatic water" and the maths is doing my head in.

If I add 2ml of bac water to 10mg, does that mean each unit on my insulin syringe gives me 100mcg? Or am I getting the units wrong there because syringes are marked in mL/iu not mcg.

My plan was 250mcg twice a day for an Achilles tendon that's been nagging me for months, so I need to know how much to actually pin. Also do I keep the mixed vial in the fridge and how long is it good for once it's mixed?

Sorry if this is a stupid question, I've read a few posts on here but everyone seems to just say "do the maths" without actually showing the working.

Comments

  • steph414: Not a stupid question at all, the unit/mL/mcg thing trips up almost everyone on their first vial. Quick walkthrough so you can see it. 10mg = 10,000mcg. If you add 2mL of bac water, you're spreading those 10,000mcg across 2mL, so concentration is 5,000mcg per mL. On an insulin syringe marked to 100 units, 1mL = 100 units, so each tick is 50mcg in your setup. 250mcg = 5 units, which lines up with what you said. Fridge storage, yes. Mixed vials are generally considered usable for around 2-4 week
  • data_labrat: Yeah steph covered the math pretty clean, ill just add the part that bit me early on. I found it way easier to figure out my dose first then back into how much water to add. If i want 250mcg at 5 units on a 100 unit syringe thats 50mcg per unit which means i need 5000mcg per mL. So 2mL bac for a 10mg vial is the move for your dose.
  • fasted_scientist: Cheers, that actually clicks better working backwards from the dose like that (ngl that’s where my brain kept tripping up). I’ve gone with 2ml bac so I’m landing at the same 50mcg per unit you described, so 5 units gets me my 250mcg twice a day. Just pinned my first dose subq near the Achilles, no drama. How long are you keeping your mixed vials before you toss them, fridge the whole time?
  • fasted_scientist: Cheers mate, that's exactly the breakdown I needed. The 5 units for 250mcg makes sense now I've seen it written out, I was confusing myself by treating the syringe ticks as if they were mcg directly. One thing though, you said 2-4 weeks, I won't get through a 10mg vial anywhere near that quick at 500mcg a day. Going to be using it for a couple months at least. Is the fridge limit a real bacterial stability thing or more of a "play it safe" line people repeat, because I'd rather not waste the re

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