Apothecary measurements

Nurses Medications

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I Am going to start nursing school in Jan. One of our professors wants us to know dosage calculations before we begin. I've been working through the book and came across the apothecary measurements and it says they are strongly discouraged and/or not used. In my mind, I don't want to learn them in the case that I receive an order in apothecary measurements and *think* I know the conversions but dont and incorrectly calculate and administer a drug. Our professor has practice problems with apothecary orders on them so obviously I'll need to learn them, but it's clearly outdated and discouraged so why have us learn something that isn't/shouldn't be used??

I can see if they have a reference book with conversions at a nursing station but I happen to strongly disagree with learning the INCORRECT way because in a stressful situation, you may recall learning something but it happens to be something you learned NOT to recognize/accept.

Experiences nurses, thoughts??

Just work through the BS that is nursing school - do what you're told - and it'll all be okie at the end. Don't sweat this small stuff.

PS you will never get an order in apothecary measurements

Specializes in retired LTC.
Just work through the BS that is nursing school - do what you're told - and it'll all be okie at the end. Don't sweat this small stuff.

PS you will never get an order in apothecary measurements

Altho this is an antiquated system, there still may be a dinosaur practitioner out there who likes the old way.,

Really, was not too long ago, that you could readily find orders written for aspirin/tylenol gr X (as in grains ten). That way you also had to know old Roman numerals among everything else.

Maybe in another 20 years or so, when all medical records are electronic, there will not be any way to enter any old systems. Until then, if they want you to know apothecary, just do it. It really isn't too difficult.

Specializes in pediatric.

Apothecary measurements are rote memorization. Like previous poster said: suck it up for the sake of school and know you will likely never get an order in this format. ;)

Specializes in Critical Care.

It's sort of an unfortunate hazing process for Nursing, you'll find that 'grin and bear it' will apply to much of your Nursing school experience.

You are correct that you should refuse any order written with apothecary measurements, but until then you'll have to deal with them. I can't guarantee you'll be free of punishment, but I like to think Nursing students are free to protest learning bad practices.

Specializes in ICU.

Had to learn them back in the 80's, but rarely see them used. Have had docs write gr X, or something in grams, but this is really not an issue today. As far as Roman numerals go, you should learn that anyway; the Roman numeral system is used in lots of other stuff. I remember learning that way back in grade school.

Specializes in Trauma, Teaching.

The biggest use of apothecary is that the general population uses ounces, pounds, etc. Being able to translate apothecary to metric for charting purposes, or metric into understandable amounts for your patients is what you will use it the most for. Docs very rarely order in apothecary, I don't even ask students to memorize grain conversions anymore. Ounces or cups to mLs, yes.

So if a mom says how much should the baby drink, and the amount you want in is 30-60 mls, you have to be able to tell her 1 to 2 ounces. Pt says he lost about a cup of blood, 240 mLs for the I/O column.

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

Sigh....yes....Apothecary is still unbelievably taught in school for the purpose of having you do the math and conversions. AND to drive you crazy.....know your conversions!

1 fl oz = 30 mL

1 cup (8 fl oz) = 240 mL

1 pint (16 fl oz) = 480 mL

1 quart (32 fl oz) = 960 mL

1 gallon (128 fl oz) = 3800 mL

1 teaspoon = 5 mL

1 tablespoon = 15 mL

1 oz = 30 g

1 lb (16 oz) = 480 g

15 grains = 1 g

1 grain = 60 mg

1 scruple =

20 grains (gr)

60 grains = 1 dram

8 drams = 1 ounce

1 ounce = 480 grains

16 ounces = 1 pound (lb)

60 minims = 1 fluidram

8 fluidrams = 1 fluid ounce

1 fluid ounce = 480 minims

16 fluid ounces = 1 pint (pt)

1 g = 15.43 grains

1 grain = 64.8 mg

1 mL = 16.23 minims

1 Minim = 0.06 mL

1 oz = 28.35 g

1 lb = 453.6 g (0.4536 kg)

1 kg = 2.2 lb

1 fluid oz (fl oz) = 29.57 mL

1 pint (pt) = 473.2 mL

1 quart (qt) = 946.4 mL

0.1 mg = 1/600 grain (gr)

0.12 mg = 1/500 gr

0.15 mg = 1/400 gr

0.2 mg = 1/300 gr

0.3 mg = 1/200 gr

0.4 mg = 1/150 gr

0.5 mg = 1/120 gr

0.6 mg = 1/100 gr

0.8 mg = 1/80 gr

1 mg = 1/65 gr

1 kg = 1000 g

1 g = 1000 mg

1 mg = 1000 mcg

Thank you all. It is very frustrating but I know that's going to be a part of this (and any) profession. I appreciate your feedback, I hope you all had a happy Thanksgiving!

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
Thank you all. It is very frustrating but I know that's going to be a part of this (and any) profession. I appreciate your feedback, I hope you all had a happy Thanksgiving!
Why is it frustrating? You actually use the apothecary system in converting lbs to Kg a common calculation. The drams and miminum and grains are not really common any more but you still have to learn them.

You will see some and like someone just said it was common to See Tylenol Xgr ordered. SOme narcotic suppositories (Like B&O)still may have grain on them.

The fact that physicians still use a system whose use has been discouraged is frustrating. It could lead to miscalculation and incorrect administration of drugs. I don't like being forced to learn and tested on an antiquated system that isn't/shouldn't be used.

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
The fact that physicians still use a system whose use has been discouraged is frustrating. It could lead to miscalculation and incorrect administration of drugs. I don't like being forced to learn and tested on an antiquated system that isn't/shouldn't be used.
It isn't used in practice anymore. Orders need to be written according to certain standards. Testing you on this is testing you on the math....can you memorize and perform the calculation of the question. Pharmacists still learn the system as well.

This is only the first of many frustrations that you will find in medicine. It is important that you learn to pick your frustrations and battles. Just like in math will you ever use pi? probably not but it is important to know the math and concept.

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