Method for preparing penicillin

In theory, you are absolutely right, but in practice, you can't. You melt penicillin with 8ML of water, and when you take it out, it will increase in volume because of penicillin (this is the most easily overlooked problem! ), make your volume greater than 8ML. At this time, if you only need 4ML, then penicillin will not have 40U units.

When I used it in clinic, it was like this: for example, there is a penicillin with 80U units, and now it needs infusion, and it needs 40U units. I first draw 6ML of normal saline to melt it, and then draw it all into the syringe. At this time, the total * * * is greater than 6ML, but this is 80U units of penicillin. I added normal saline to 8ML, the volume increased and the concentration diluted.