Please, HELP on MATH!!!

[jamhoyz]

Hi everybody I have been trying to solve these math problems for hours and hours and I can't get to the right answer.I am freaking out, even getting a headache now:madface: PLEASE, I REALLY NEED HELP RIGHT NOW, IF YOU GUYS CAN PLEASE HELP ME. The math problems are listed below. Thank you very much, I really appreciate it!!!!Thanks again.

1. Order 35 mg of medication by mouth t.i.d.

Patient weight: 99 pounds.

Safe dose range: 2 to 4.

This is the correct dose range.

2. Child's BSA: 0.62 m2, 3 years old.

Order: Betamethesone 25 mg/m2/day PO, divided into four doses.

Available: Syrup 2mg/mL in 25 mL vial.

How many mL will you administer per dose.

Correct answer: 15.5

[midnight*sky]

First, are you sure the answer to #2 that you provided is correct? It doesn't seem so to me, but maybe I am wrong too!

[Daytonite, BSN, RN]

1. order 35 mg of medication by mouth t.i.d.

patient weight: 99 pounds.

safe dose range: 2 to 4.

this is the correct dose range.

safe dose range: 2 to 4

?

2 to 4 what? no other parameters are given. this problem, as given, is incomplete and the answer cannot be calculated.

2. child's bsa: 0.62 m2, 3 years old.

order: betamethesone 25 mg/m2/day po, divided into four doses.

available: syrup 2mg/ml in 25 ml vial.

how many ml will you administer per dose.

the given answer 15.5 (assumed to be 15.5 ml) is incorrect. the 15.5 ml has not been divided into 4 doses. i get 3.875 ml. which would be rounded off to 3.9 ml.

25 mg/ m

(dose desired)

x 0.62 m

(child's bsa)

/4

(number of doses per day)

x 1 ml/2 mg

(dose on hand)

= 3.875 ml/dose

, rounded to

3.9 ml/dose

correct answer: 15.5

[jamhoyz]

Hi thank you so much, I appreciate it. I justed wanted to know if there is a specific formula to solve these types of problems. Because I have noticed that people solve these problems differently every time. Let's put different numbers into the problem, would I solve it the same way. If you can tell me, I would appreciate it! Thanks again.

[Daytonite, BSN, RN]

dose desired divided by the dose on hand multiplied by the amount that the dose on hand comes in.

that is the formula i was taught years ago and the same one used today although i have seen it worded a bit differently in other places. there are weblinks to medication math tutorials listed on post #2 of this sticky thread: https://allnurses.com/general-nursing-student/nursing-math-thread-264395.html - the nursing math thread that will have these formulas.

i use dimensional analysis (factor labeling) which is an arithmatic manipulation to do the math part of the problems and organize the labels with the numbers, but i still keep track of the dose desired, dose on hand and amount that the dose on hand comes in relationships in when working on the problem.