Medication Conversions

Nursing Students Pre-Nursing

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Can someone please help me with this, I'm not sure how to do medication conversions, I'm not sure if I'm even describing it right. How do you do conversions, or memorize them.

For instance:

425mg equals how many grams?

1.5 Ounces equals how many mililiters?

Gr.1/4 equals how many milligrams (mg)?

Whats the formula if any in doing conversions of medications? I don't remember how to convert from grams, mililiters etc. Please help.

Thanks

Specializes in OR, Telemetry, PCCU, Med/Surg.

1g = 1000mg so 1mg = 0.001g

1kg = 1000g = 1 000 000mg

1l = 10dl = 100cl = 1000ml

1 ounce = 28.35g

If you can't remember, there are tons of websites with conversions on them. Try www.onlineconversion.com

Specializes in being a Credible Source.
...I'm not sure if I'm even describing it right. How do you do conversions...

Strictly speaking, what you're doing are unit conversions.

I'm a big fan of Google for unit conversions.

Specializes in DOU.

1 grain = 60 mg

1 ounce = 30 ml

For converting gram to mg, move decimal 3 spaces to right

For converting mg to gram, move decimal three spaces to left

For converting mg to mcg, move decimal three spaces to right

Can someone please help me with this, I'm not sure how to do medication conversions, I'm not sure if I'm even describing it right. How do you do conversions, or memorize them.

For instance:

425mg equals how many grams?

1.5 Ounces equals how many mililiters?

Gr.1/4 equals how many milligrams (mg)?

Whats the formula if any in doing conversions of medications? I don't remember how to convert from grams, mililiters etc. Please help.

Thanks

Do you have a book you are using? Are you trying to learn this on your own or is this for a class? I only ask because these are the most basic things you learn, they are quite easy once you practice a few. If your trying to learn on your own, the first thing you need to do is memorize the basic equivelents

1. how to get from mg to grams. your dividing so you move decimal 3 places to the left. 425mg =.425grams

2. 1.5oz = ?ml you set these problems up using dimensional analysis

you memorize how many oz=1ml 30ml=1oz then you set the problem up using that equivalent.

1.5oz X (unit you are converting to this case 30ml)divided by the 1oz

the oz cancel and your left with 45ml

3. same thing witht the grains to mg gr1= 60mg. use dimensional analysis to solve.

gr 1/4X 60mg/gr1 =

the key here is to memorize your equivelants once you do that every problem is the same.

good luck.

A cool way we were taught to convert from units of say grams to milligrams etc was this:

First you have to know bigger to smaller measurements for example:

Kilos, grams, milligrams, micrograms.

Then are you converting from larger to smaller? Think of the L in Larger..the bottom part of the L is pointing you in the direction the decimal place must move. For each measurement you are moving you move the decimal point 3 places. Going from kilograms to milligrams..you are going from a Larger measurement to a smaller one so the L is pointing you in the correct direction (to the right). Ok, so now you know which way the decimal is going..now you need to know how many times you must move it. Kilos to grams (3 places) grams to milligrams (3 places) now you know you are moving the decimal in the kilo measurement 6 places to the right.

The same can be done for converting smaller measurement to larger ones. The S in smaller also points you in the direction you are to move the decimal point..to the Left (see where the bottom part of the s is going..to the left). Then again, you figure how many spots to move it. Volia' your done.

You do have to memorize the basic measurements from Larger to smaller k, g, mg, mcg..and so on.

To remember grains to milligrams think of a clock. 15mg is 1/4 grain, 30 mg is 1/2grain, 45mg is 3/4grains and 60mg is 1 grain. 15 minutes after is quarter after, 30 minutes is 1/2 hour, 45 minutes is 3/4' of an hour and 60 minutes is 1 hour.

When ever I have conversion tests I always put the L and S at the top of the page, write down the order the measurements go larger to smaller and I put a clock on the paper marked with the 1/4hr, 1/2hr, 3/4hr and 1hr and inside put the corresponding conversion...

Hope all that babbling helped some.

A cool way we were taught to convert from units of say grams to milligrams etc was this:

First you have to know bigger to smaller measurements for example:

Kilos, grams, milligrams, micrograms.

Then are you converting from larger to smaller? Think of the L in Larger..the bottom part of the L is pointing you in the direction the decimal place must move. For each measurement you are moving you move the decimal point 3 places. Going from kilograms to milligrams..you are going from a Larger measurement to a smaller one so the L is pointing you in the correct direction (to the right). Ok, so now you know which way the decimal is going..now you need to know how many times you must move it. Kilos to grams (3 places) grams to milligrams (3 places) now you know you are moving the decimal in the kilo measurement 6 places to the right.

The same can be done for converting smaller measurement to larger ones. The S in smaller also points you in the direction you are to move the decimal point..to the Left (see where the bottom part of the s is going..to the left). Then again, you figure how many spots to move it. Volia' your done.

You do have to memorize the basic measurements from Larger to smaller k, g, mg, mcg..and so on.

there is a great little mnemonic for this too

king

henery

doesn't

usually

drink

chocolate

milk

I read that the usually will be your units your working with, grams, liters etc...

you set it up in a line

K H D d c m

now say you have 20 mg to g=.02g

put the 20mg under the m and cound decimals back to the U (grams)

45.5 deci grams to mg.

45.5 under the d and count two spaces to the right 4550 mg

I used this when I hadn't done the metric conversions in a while, soon it becomes second nature but that mnemonic is good in a pinch lol

Specializes in med/surg, telemetry, IV therapy, mgmt.

to do conversions you have to refer to a chart or memorize the conversion equality that pertains to the unit of measures you are dealing with. there is no other way. i posted links to several conversion charts on post #3 on this thread of allnurses. what you need to do is download or copy one or more of them, make flashcards and memorize some of these conversions. for tests, you will have to know them from memory. the more you work with them, the better you will get at remembering them:

if you want to see drug calculation problems that are worked out that have conversions in them, see some of the posts on this thread:

Specializes in ICU.

Knowing how many micrometers are in a meter and such is basically just finding a trick to make you remember the order

(I was a product of the 80's and so I made up a little sentence about a "Megadeath" (the band) concert...lolNot a fan, but it worked.

Converting this much of one is how much of another is easiest once you learn the unit conversion thingy

25 g is how many mg?

put the 25 on top of a fraction in the first set of parenthesis and then the conversion factor in the second set of parenthesis so that the same unit amount is in the opposite position in the second group than it was in the first (so that they cancel) you multiply across the top and divide across the bottom.

25g 1000mg

1 1g

the g with the 25 would be canceled by the g with the 1 and so you would multiply all the numbers on top and divide by the numbers on the bottom so it's 25x1000 divided by 1

or if it was the opposite conversion 25000mg to G. This time you are multiplying the 25000x1 and then divide by 1000=25g

25000mg 1g

1 1000 mg

You know how to set it up because you have to have the units cancel and that is how you know if you divide the numbers or multiply.

DOes this make any sense? It is hard to show how this is done on a computer and much easier on paper.

NOTE: I tried to write the fractions how they should be and this program turned it into a mishmosh so I edited the info but I still don't think it lined up correctly. If you like I can email it to you.

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