Another Med Calc Question -Sorry! =(

[StarGirl]

I am stumped on one more math question. ...

A new medication, X disodium, comes as a powder which must be reconstituted as follows: For IV use: Add 24 ml of sterile water for injections, USP. Each 2.5 ml of resulting solution contains 500 mg of X. Prior to administration, dilute further to desired volume with an appropriate IV solution. How many ml must be injected into a 100 ml IV bag of NS to equal 1.5 g of X? __ ml?

I am getting too caught up in all the info and don't really know what to do with it all.

[Nursingchicka21]

2.5(1500)=500x

3750=500x

7.5=x

7.5 ml

[Daytonite, BSN, RN]

a new medication, x disodium, comes as a powder which must be reconstituted as follows: for iv use: add 24 ml of sterile water for injections, usp. each 2.5 ml of resulting solution contains 500 mg of x. prior to administration, dilute further to desired volume with an appropriate iv solution. how many ml must be injected into a 100 ml iv bag of ns to equal 1.5 g of x? __ ml?

pick out the important information:

dose desired

: 1.5 gram

dose on hand

: 500 mg/2.5 ml (this is the reconsituted solution)

you also need a conversion factor because you have grams and milligrams mixed together. you have to equalize them and work with one measurement.

conversion factor

: 1000 mg = 1 gram

now, do the math. you can use the formula

dose desired divided by the dose on hand multipled by the amount the dose on hand comes in to get the amount to give (or use).

you will end up with (in this case) an answer in "ml".

1.5 gram

(dose desired

)

/

500 mg

(dose on hand)

x 1000 mg

/

1 gram

(conversion factor)

x 2.5 ml

(amount the dose on hand comes in)

=

7.5 ml

(amount to inject into the 100ml bag of ns)