We have a handful of medicines that we administer by the “amp” (sodium bicarbonate, epinephrine, calcium chloride, and dextrose, for example). Clearly this is for simplicity as these are medications we use in emergent situations. That being the case, you may not spend much time thinking about the amount of medicine you are actually giving. Most have nice round numbers: D50 (50% dextrose), 10% calcium chloride, and although we don’t push this medicine by the “amp,” lidocaine comes in 1%, 2%, or 4%. But sodium bicarbonate comes as 8.4%. Weird. Why? Do you know?