For sure there is one place that grains are still being used, and that is on the medication math quizzes you will be taking in nursing school. Become familiar with the conversion factors so you don't have to relearn them and/or retake the quizzes.
Noting this from suzanne's post (I think it was suzanne....)
they gave grams of tylenol to a 2 year old. Next thing, the child was being treated for a tylenol overdose
This is terrible and could have been avoided if either of the nurses had been familiar with the dosing guidelines of the drug, which they should have been, or looked it up, since they didn't know proper dosing for the drug. They, as nurses, were responsible for what they gave, legally. They "did harm" in a manner consistent with malpractice, by a direct act, which would be assault and battery.
You won't have that problem because you are going to learn lots of good stuff about commonly prescribed medications, and before you give a patient anything at all, you are going to rehearse mentally whether the drug is safe to give, and mostly because you will call the pharmacist if you have a med question, and hold the dose until you verify with the physician that he meant grams instead of grains.....
I know this because you are already thinking about practicing nursing and you aren't in nursing school yet. Good for you!