Drug calculation HELP!

Editorial Team / Admin · Feb 1, 2015

There isn't really a set formula to solve this problem. However, there are different methods that you can use to find the right answer. My personal favorite is dimensional analysis. Here's a quick review of it: Math Skills - Dimensional Analysis

So once you view that webpage, why don't you come back and show us the work you've done. If you get stuck, that's okay- but we want to see you do the work so we can give you the appropriate help and to show us where exactly you get stuck.

mocha111 · Feb 1, 2015

is it dose orders DIVIDED by dose available TIMES Volume

= 1250 DIVIDED by 25000 TIMES 1000 = 50... so would it be 50ml an hour i would administer

jadelpn, LPN, EMT-B · Feb 1, 2015

You can look at calculations as what you want and what you need. If you HAVE 25000/1000 and you need 1250/X and cross divide. I am a math idiot at best--so I have to justify it this way.

But, in practice, ALWAYS have a second RN check your math when you need to mix your own meds, especially with a med such as heparin.

Best wishes!

nurseprnRN, BSN, RN · Feb 1, 2015

Think about what you have in your hand, and think about what you need to know.

You have 25,000 units in 1000 cc. How many units are there in 1cc? Do you know how to figure that out? 25,000units/1000cc ...?

OK, so it's 25 units/cc.

So you want to give 1250 units/hour. How many cc is that?

1250 units / 25 units per cc = 1250 units per 50cc.

See, medication calculations are just word problems. There's nothing magic about the arithmetic and basic algebra needed to solve them. Here's an example that might look less scary:

You have 25,000 jellybeans in 1000 little baggies. How many jellybeans are there in each bag?

You want to give 1250 jellybeans to your niece's school party. How many little baggies is that?