Dosage calculations exam -rounding

[PCU RN]

ok the problem i'm given:

admin 0.003mg PO. available 0.05mg/ml.

i come up with an answer of = 0.06ml

would i round the 0.06 to 0.1ml or actually give 0.06?

test is tomorrow so any advice is greatly appreciated!!

[AgentBeast, MSN, RN]

You aren't going to be able to accurately measure out 0.06mL. Usually you'd round up to the nearest 0.1mL. Even then you'd have a heck of a time trying to measure out 0.1mL of a PO medication.

[violettn, ADN]

I was having problems remembering all the rounding rules, so I mad this cheat sheet... hope it helps! :-)

Injections: When giving more than 1 mL:

Calculate to the hundredth and round to the tenth:

1.26 mL = give 1.3 mL

1.75 mL = give 1.8 mL

Injections: When giving less than 1 mL:

Calculate to the thousandth and round to the hundredth:

0.823 mL = give 0.82 mL

0.666 mL = give 0.67 mL

Oral Medications: SCORED Tablets

Calculate to the tenth and round to the nearest half tablet:

1.5 tablets = give 1 1/2 tablets

1.7 tablets = give 2 tablets

Oral Medications: ALL other oral pills

Calculate to the tenth and round to the whole number:

1.4 tablets = give 1 tablet

1.9 tablets = give 2 tablets

Oral Medications: Oral LIQUIDS:

Calculate to the hundredth and round to the tenth:

2.32 mL = give 2.3 mL

2.36 mL = give 2.4 mL

IV Problems: When calculating drops or drop factor:

Calculate to the tenth and round to the whole number:

4.4 gtt/min = give 4 gtt/min

IV Problems: When calculating mg/min, mcg/hr, mL/hr , units/mL

Calculate to the hundredth and round to the tenth:

1.45 mg/min = give 1.5 mg/min

20.25 mcg/hr = give 20.3 mcg/hr

2.12 mL/hr = give 2.1 mL/hr

20.35 units/mL= 20.4 units/mL

Adult Body Weight:

Calculate to the hundredth and round to the tenth:

7.35 kg = 7.4 kg

[Vershonda]

I would give 0.06ml but usually the dosage calculation exams will tell you how to round problems. if less than 1 round to hundredths and more than 1 round to the tenths. These were always the rules.

However, Violettn has a good example on what to do...

[PCU RN]

thanks! no more questions!

[virgo,student nurse, CNA]

Great cheat sheet. I m going to print. Thank you

[SpaceCowgirl, BSN]

I have a question about the rounding rules for scored tablets. On my med calc quiz, this was the only question I missed, and I still don't understand why.

Order: Atarax 36 mg PO daily

Available: Atarax 10 mg scored tablets

How many Atarax tablets should be given daily?

The answer came out to 3.6, so I answered 3.5 tablets, but this is the answer they gave:

tabs = 1 tab X 36 mg = 3.6 = 4 tabs

day 10 mg day

Rounding rules:Calculate to the tenths place and round to

the nearest half tab.

So my question is, when do you round to the half tablet? Only when it comes out to exactly .5? So 1.0-1.4 would be 1 tablet and 1.6-2.0 would be 2?

[SpaceCowgirl, BSN]

I have a question about the rounding rules for scored tablets. On my med calc quiz, this was the only question I missed, and I still don't understand why.

Order: Atarax 36 mg PO daily

Available: Atarax 10 mg scored tablets

How many Atarax tablets should be given daily?

The answer came out to 3.6, so I answered 3.5 tablets, but this is the answer they gave:

[TABLE=class: cms_table]

[TR]

[TD]tabs = 1 tab X 36 mg = 3.6 = 4 tabs[/TD]

[/TR]

[TR]

[TD]day 10 mg day[/TD]

[/TR]

[TR]

[TD]Rounding rules:Calculate to the tenths place and round to[/TD]

[/TR]

[TR]

[TD]the nearest half tab.

So my question is, when do you round to the half tablet? Only when it comes out to exactly .5? So 1.0-1.4 would be 1 tablet and 1.6-2.0 would be 2?[/TD]

[/TR]

[/TABLE]

[Kuriin, BSN, RN]

In my pharmacology class, our teacher drilled it into our heads that you round up in a 3.5, but only on drugs where you know you won't have a disaster if you give higher than the dose prescribed. For your question, yes, you would round up because 3.5 is LESS than what is prescribed thus you may have problems with therapeutic effects.

[SopranoKris, MSN, RN, NP]

Our program rounds down if 0.0-0.4 and rounds up if 0.5-0.9

KristinCarter said:

I have a question about the rounding rules for scored tablets.

Order: Atarax 36 mg PO daily

Available: Atarax 10 mg scored tablets

How many Atarax tablets should be given daily?

KristinCarter said:

I still don't understand why.

Talk to your instructor.

"Rounding to the nearest half-tab" would indeed yield 3-1/2 tablets (until you reach 3.7... at which point you'd round to 4).

3.1 - 3.3 = 3 tabs

3.4 - 3.6 = 3-1/2 tabs

3.7 - 3.9 = 4 tabs

Each of these has three real values (real value meaning with a decimal point as opposed to a whole number) so none is over represented compared to the others.

IRL, I'd speak to the doc about adjusting the order precisely match the available doses.

[SpaceCowgirl, BSN]

well, just got finished speaking with the instructor - she said in real life situations it will be different, but for testing purposes, 3.0-3.4 = 3 tablets, 3.5 = 3.5 tablets, and 3.6-4.0 = 4 tablets