Drug calculations

bburnette252

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So I am almost done with EMT school, hopefully by the end of this month I'll be holding that certificate.

But I'm still having trouble with drug calculations, could anyone give me any pointers?

We can use Epi as an example, my states dosage for Epi is 0.3 to 0.5 every 5 minutes if no relief. Can anyone help me calculate the dosage for the patients weight? Or show me how you do it in the field?

I have never been good at math and this is holding me back.

Thanks!
 

Handsome Robb

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Well what's the concentration of epi you're using?

1:10,000 is 1mg in 10mL for a concentration of 0.1mg/mL. so .3-.5 mg would be 3-5mL

1:1000 is 1mg in 1mL so you answer this one.
 

STXmedic

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Why do you need the patient's weight? It's 0.5mg, not 0.5mg/kg.
 

Handsome Robb

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dose in vial/volume of vial X desired dose/x, solve for X.
 

Handsome Robb

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Then, if you've got a weight based calculation you still need to find the concentration.

So you've got dose in vial/volume in vial = x/1mL solve for x and you have your concentration. so say you've got 10mg/5ml that means you have 0.5mg in 1 mL.

Now multiply your dose by the weight say 1mg/kg as an example in a 50kg person, that's 50mg. Because you know your concentration and how much drug is in 1 mL you can now use the original formula I gave you to find the volume you need to give.

so you've got 50mgx0.5= 25 mL

Does that make sense at all?

The more you do it the easier it gets, 99% of my drug calcs are in my head then checked with simple math on a scratch sheet of paper or if my phone is handy and my hands aren't nasty I'll use the calculator.
 

Medic Tim

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So I am almost done with EMT school, hopefully by the end of this month I'll be holding that certificate.

But I'm still having trouble with drug calculations, could anyone give me any pointers?

We can use Epi as an example, my states dosage for Epi is 0.3 to 0.5 every 5 minutes if no relief. Can anyone help me calculate the dosage for the patients weight? Or show me how you do it in the field?

I have never been good at math and this is holding me back.

Thanks!

That is very similar to my treatment guidelines. If the pt is <80 kg they get 0.3 mg. If > 80kg they get 0.5mg.

Epi for injection is a 1: 1000 concentration, meaning 1 gram in 1000 ml . Most epi amps are 1 mg in 1 ml. You do not need to do a weight based calculation unless you have a ped pt. They usually get 0.01mg/kg to a max of 0.3mg q 5min.
 

Handsome Robb

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That is very similar to my treatment guidelines. If the pt is <80 kg they get 0.3 mg. If > 80kg they get 0.5mg.

Epi for injection is a 1: 1000 concentration, meaning 1 gram in 1000 ml . Most epi amps are 1 mg in 1 ml. You do not need to do a weight based calculation unless you have a ped pt. They usually get 0.01mg/kg to a max of 0.3mg q 5min.

edited because I'm an idiot and read that wrong. read 1gm in 1ml hahah

So that's where the 1:1000 comes from.
 
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