# Pediatric medication calculation

1. Hello,
So I'm working with my virtual ATI coach for my NCLEX and I'm currently on pediatrics. I have a medication calculation that I'm stumped on and after reviewing my medication administration textbook, I'm still not getting this question. Can someone help me with this? Thank you so much

" A nurse is preparing to administer ampicillin 25mg/kg PO divided in equal doses every 12 hours to an adolescence who weighs 99 lbs. The amount available is ampicillin suspension 50mg/5ml. How many mL should the nurse administer per dose? Round to nearest whole number. 56ml

After converting from 99 lbs to kg I got 45kg.
I then multiplied 25mg by 45kg and got 1125mg/45kg.
I then divided the 1125 mg by 2 since this med is taken every 12 hours in equal doses.
I got 562.5mg per dose.
The med is available in 50mg/5ml, so I divided 562.5 by 50mg ad got 11.25.
Last I multiplied 11.25mg by 5ml and got 56.25
Then rounded down to 56ml.

Joined: Jun '18; Posts: 3
from CA , US

4. Your calculations are correct and I agree it looks weird but it's right. The issue is they are using a pediatric format (suspension) for a patient who has achieved an adult weight. In the real world (if the patient can swallow pills) he would be given Ampicillin 500mg BID in a tablet/capsule format. But of course this is NCLEX land so there's that. The pediatric suspension is really formulated for little kids so administering it in adult doses is going to seem like an abnormally large volume. If it helps try to think of it as about 3.5 tablespoons. In my brain that doesn't seem as high a volume. When I worked in peds and took care of some of our older severely disabled patients with g-tubes we would often get ginormous bottles of medications in suspension form due to the weight of the patient and the concentration of the medication.
5. chare,
Thank you so much for the reply, yeah it didn't seem right to me as well so I was second guessing myself when it came to the math. Thanks again
6. Wuzzie,
Thank you for the reply! I went over this problem so many times and even consulted my old medication textbook b/c I felt I must have been doing something wrong. But you're right, this is NCLEX land and I've been doing countless practice questions, some seem so irrelevant but I gotta do what I can do pass. Thanks again
7. In the real world, this dose would be administered as a tablet. Even if it's a tube fed developmentally delayed adolescent, I think it's still more likely for the dose to be administered as a tablet and crushed.
8. Quote from Merokim042382
Wuzzie,
Thank you for the reply! I went over this problem so many times and even consulted my old medication textbook b/c I felt I must have been doing something wrong. But you're right, this is NCLEX land and I've been doing countless practice questions, some seem so irrelevant but I gotta do what I can do pass. Thanks again
You're doing fine. And as an old nurse to a newbie please always keep this same level of, for lack of a better term, scrutiny in your practice once you become a nurse. If something seems off...investigate and confirm. Take your time and use your resources to provide competent AND excellent care. Good luck to you in your future endeavors.