As your research subjects titrate up do you add less BAC?

I can't cover every point but here's what I'm doing now. I draw from a 30 mg vial and switched the last one to only 2 ml BAC instead of 3 ml. That cuts the injection volume and I haven't seen any problems. You didn't mention your own dose so I can't compare directly.

I do adjust. With 50 mg vials I started with 2 ml and have since moved to 1 ml while climbing to 8 mg weekly. I prefer 10 units over 20-plus units. It's a personal choice. I try to keep any subcutaneous injection at or below 25 IU, though NAD and a couple other larger-volume items are exceptions.

Yes, you can and should change the BAC amount as the dose increases. I aim for 50 units or 0.5 ml per injection. A peptide calculator helps keep the numbers accurate if needed.

When I used compounded product the pharmacy used a single fixed strength of 10 mg per ml. At the top recommended weekly dose that meant drawing 150 units and needing two syringes. Once I switched to research sources I changed the approach. Now I use 60 mg vials mixed with 2 ml BAC for a 30 mg per ml strength, bringing the dose down to 50 units.

Yes, up to a point. I've seen reports that very high concentrations can cause interactions, and this seems to differ depending on the peptide.

I choose BAC volume based on two things: keeping the math straightforward and landing injection volumes that are easy to measure accurately without being unnecessarily large. At low doses a bigger volume can help with precise measurement on the syringe. At higher doses you don't want excessive volume that might increase irritation at the injection site. For most peptides I aim for a 10 mg per ml ratio so the math stays simple. If a vial actually contains 23 mg I add 2.3 ml; then 0.5 mg is 5 IU and 2 mg is 20 IU. Since my current doses are still on the lower side, accuracy at small volumes matters more. At 20 mg you wouldn't want to draw 100 IU twice, so that concentration wouldn't work well.

My subject handles 100 units of the peptide plus 100 units of NAD+ without any trouble.

I like my injections between 15 and 30 IU but will go up to 50 IU, so I add BAC accordingly. I usually aim for at least 1 ml per vial. When a vial has much smaller doses than I need, I add 1 ml to the first vial, draw it out, add it to the next vial and repeat until the concentration supports my preferred injection volume.

I don't aim for one specific concentration. I just try to keep the current GLP-1 dose between 10 and 50 IU. I also split the injection across a couple of nearby sites to reduce site reactions, and that has worked well so far.

I began noticing site reactions once volumes reached 0.2 ml and then 0.3 ml. It may be that the extra liquid is the issue, so the most recent vial I split into two shots of 0.2 ml and 0.1 ml.

I have a 60 mg vial and am using 8 mg, yet I still add 3 ml. Next time I'll try 2 ml instead.

Thanks for the details. I agree and want to stay under 25 or 30 IU. I use a peptide calculator and a spreadsheet to track everything and stay very careful. I'll change future reconstitutions to match. The knowledge shared here is consistently high quality and helpful.

Short answer: yes.

That 30 mg per ml strength matches the brand-name product concentration used for the 15 mg dose in their pens.

The only peptide I mix with more than 1 ml BAC is one particular copper peptide; everything else gets 1 ml, including the 60 mg vials used for 15 mg weekly doses. That results in roughly 23 units per injection even when the vial is slightly overfilled. No negative effects have shown up at that concentration.