tiffany311 (New Member)

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I am hyperventilating. Converting is really foreign to me and I know that it is vital to know it in the health field, I fear that I am going to fail medical math. As I don't know how to convert anything:(

Here is a problem that I am trying to work out and I can't, I am on the verge of crying:(

Your client is receiving 1500mcg of benztropine mesylate, an antiparkinson drug. The drug comes in 0.5mg tablets. How many tablets should you administer?

Thank you!

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There are 1000mcg in 1mg. So 1500mcg of a med is 1.5mg. So you would need 3 0.5mg tablets to get the 1.5mg which is the same as 1500mcg. There is an allnurses member whose screen name is Daytonite and provides excellent explanations to students questions. Try going back and looking for similar math calc threads and see if you can find a "Daytonite" explanation

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Hi,

if I don't remember which way to move the dec. point , I always write it out like this

you know that:

1mg = 1000mcg

write underneath what you have on hand

0.5mg = ? mcg

now cross multiply and divide

0.5 x 1000 / 1 = 500 mcg

So this is how much it is in mcg for one tab. Now , of course: 1500 : 500 = 3

So you need 3 tabs.

The easier way , would be to remember , that you can move the decimal point 3 spaces to the right , if you have a smaller measurement, or 3 spaces to the left , it it is larger.

I hope this helps.

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Do you have a med calculations book? Have you thought about going in for some math tutoring?

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I cannot afford a tutor, just a poor student barley scraping by:(

where would I pick up a medical calculations book?

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Your school's bookstore SHOULD have one for the nursing students. We were required to have it. Tutoring...I just mean going in and talking with your instructors.

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I cannot afford a tutor, just a poor student barley scraping by:(

I imagine one of your classmates would be more than happy to sit with you and help you. I've done it several times with my friends. And learning the conversions is essential....Good luck!

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I cannot afford a tutor, just a poor student barley scraping by:(

where would I pick up a medical calculations book?

here you go:

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your client is receiving 1500mcg of benztropine mesylate, an antiparkinson drug. the drug comes in 0.5mg tablets. how many tablets should you administer?

the formula you should use is the dose desired divided by the dose on hand equals the dose to give. you will need to apply a conversion factor because your dose on hand is in mg and the dose you want to give is written as mcg. you need to know that there are 1000 mcg in each mg.

dose desired: 1500 mcg

dose on hand: 0.5 mg

conversion factor: 1000 mcg = 1 mg

set up the problem according to the formula.

1500 mcg
(dose desired) /
0.5 mg
(dose on hand)

to deal with the problem of the mcg and mg (labels) on these numbers the easiest way is to use dimensional analysis so that all the labels on the numbers are going to factor, or cancel out. this means that you have to know how to work with fractions and that to cancel out labels you must have one label in a numerator and it's mate you will cancel out in must be in a denominator. when you apply the conversion factor to the equation you can put the mcg or mg in the numerator or denominator of the fraction it is in, which ever suits your needs in manipulating the equation. however, 1000 mcg = 1 mg is a relationship, like a marriage, that must not be separated and these two numbers must remain together in a fraction because together they are equivalent to each other. in effect, the fraction they represent can be reduced to the number 1. a basic math concept is that any number multiplied by 1 = itself.
conversion factors are, in essence, tricked out number 1's when you are using them in equations
. so,:

1500 mcg
(dose desired) /
0.5 mg
(dose on hand)
x 1

multiplying this fraction by the 1 has absolutely no effect on it at all. however, lets substitute the conversion factor for the number 1 because the conversion factor is a unit of 1, and we now have

1500 mcg
(dose desired) /
0.5 mg
(dose on hand)
x 1 mg/1000 mcg
(conversion factor)

do the math and cancel out the labels that are repeated in the numerators and denominators and you end up with an answer of
3

the meaning of this answer is that you would give
3 tablets
.

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websites:

books:

math for nurses: a pocket guide to dosage calculation ...

most schools have tutoring services-just ask instructor!

books often available at school library for onsite use..occasionally take home overnight or 1wk loan---librarians are great to get advice from!

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Another book you might want to check out is Calculating with Confidence. I took an online course at a community college last spring for \$25 (you did not get credit for the class) and this was the text book we worked from. Truth be told, the class was not completely necessary because I felt you could teach yourself from the book!

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dose/ have.

1500 mcg=1.5 mg(dose)

0.5 mg(have)

1.5 mg/0.5 mg = 3 tablets.