med dosage calculation

elijahvegas, ASN, RN, EMT-P · Apr 28, 2015

Ac = mealtime = 3 meals a day

hs = bed time

So thats 4 times a day

You can figure the rest out from there

Mavrick, BSN, RN · Apr 28, 2015

Doing two things wrong.

There is a knowledge error as PP has pointed out. Look up what a.c. and h.s. mean. They are Latin abbreviations that you will see again.

And a math error. 60 x 7 does not = 42. You are off by a factor of 10. 10 times less than it should be. Your math in dosage calculation must be perfect EVERY TIME. Think it through. Your answer can't possibly be 42 because you already have 60 and are multiplying it.

dcwang · Apr 28, 2015

Got it.

ac means before meals, so it is 3 times a day.

and once before bedtime, so that's 4 times total a day.

30mg x4= 120mg/day

120 X 7= 840 mg/week

840mg= 0.84g per week, which matches the answer in the book.

i've been self-studying med math dosage before the hw's been assigned. i'm pretty nervous about the quiz.

Mavrick, BSN, RN · Apr 28, 2015

Now you got it!

Go forth and miscalculate no more.

dcwang · Apr 28, 2015

When I am being asked to give the name of the drug on a test situation, do I always need to include HCl or XR, for example, Ritalin XR or can I just give it as Ritalin?

Mavrick, BSN, RN · Apr 28, 2015

When I am being asked to give the name of the drug on a test situation, do I always need to include HCl or XR, for example, Ritalin XR or can I just give it as Ritalin?

I would use the XR (Extended Release), LA (Long Acting), CR (Controlled Release), etc when referring to that specific drug.

Some medications have different formulations. LA (Long acting), XR (Extended release) for example indicate a special formulation of a drug to make the effects last a longer period of time so you only have to take a pill once a day for example. Same drug, just "timed-released". That makes a difference in dosage and how often you take it. It also gives you a clue NOT to crush it in order to put it down an enteral tube.

For other medications the HCl is part of the chemical formula that makes the drug more easily dissolved in water and you usually only have the one formulation of the drug.

dcwang · Apr 28, 2015

How would I know that Xanax is extended release. I don't see XR on the drug label thank you so much for your help!

nurseprnRN, BSN, RN · Apr 28, 2015

the prescriber ordered propantheline bromide 30mg PO ac and hs. How many grams of propantheline bromide will the pt receive in one week?
here's what I did
30mg X 2= 60mg per day
60mg X 7= 42 mg
42mg= 0.042g/week
The answer in the book says 0.84g... I must be doing something wrong.

AC means before meals. Most people think that means three meals a day. So 30mg x 2 is not the correct dose for one day, plus you have to add in the HS dose.

60mg x 7 is not 42mg, either.

You need to read a lot more carefully.

Mavrick, BSN, RN · Apr 28, 2015

How would I know that Xanax is extended release. I don't see XR on the drug label [ATTACH]18111[/ATTACH] thank you so much for your help!

This particular preparation in NOT extended release that's why you don't see XR on the drug label.

What makes you think it is extended release?

dcwang · Apr 28, 2015

@mavrick, the answer in the book was Xanax XR, it was asking for the name of a drug that is a controlled substance. I put Xanax based on the drug label, but noticed that the answer was specifically Xanax XR

KelRN215, BSN, RN · Apr 28, 2015

@mavrick, the answer in the book was Xanax XR, it was asking for the name of a drug that is a controlled substance. I put Xanax based on the drug label, but noticed that the answer was specifically Xanax XR

Was it a multiple choice question? Both Xanax and Xanax XR would be controlled substances.