drug computation.. help!

Remember that the formula is dose ordered/dose on hand multiplied by volume/tabs.

So for number one you have .325mg/.250mg x 1 tab = 1.3 tab. Your book may have keyed that incorrectly. A way to check is see how much smaller or bigger your dose on hand is. In this case .250 is less than .325 so you know you're going to need at least 1 tab to get there.

Convert 50lbs to kg, 50lbs/2.2= 22.72. then multiple 5mg x 22.72= 113.75. Now you can continue with the formula, 113.75mg/125mg x 1ml = .91ml

I get 0.3mL for the second problem.

Hi okami i came up with the same answers but i'm just wondering why they are not included in the choices which makes me crazy like ___.

I am curious as to why you're getting 0.91mL for the second problem? If it's three divided doses wouldn't the admin amount be 0.3mL? (And it drives me crazy too when stuff is keyed wrong...though I understand things happen!)

Are you sure that you copied the questions correctly, as none of the answer choices you have provided are correct.

I am assuming that the second problem should be 50 kg instead of 50 pounds. Unless your giving a pediatric patient Dilantin.

5 X 50= 250

250/ 125= 2mL per day

2/ 3= 0.67 mL

not one of the choices

Yeah....... none of the given choices are correct. I hate it when that happens.

To everyone: yeah i made sure i copied it correctly. I was thinking about it and wonder why its none of the choices.. anyway thanks for your effort guys. At least i know i'm not the only one who came up with a different answer.

OP, regardless of what choices appear and what the answer key says, the correct answers to the questions posed are as noted below. Any deviation from the answers that I've provided are either an error of transcription or an error of calculation.

Question 1: Answer = 1.5 tablets (as shown below)

[TABLE=width: 253]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]1 tab[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center]0.375 mg[/TD]

[TD=align: center]x[/TD]

[TD=align: center]----[/TD]

[TD=align: center]=[/TD]

[TD=align: center]1.5 tab[/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]0.25 mg[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[/TABLE]

Question 2: Answer = 0.9 mL (as shown below)

[TABLE=width: 244]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]1.0 kg[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center]50 lb[/TD]

[TD=align: center]x[/TD]

[TD=align: center]----[/TD]

[TD=align: center]=[/TD]

[TD=align: center]22.7 kg[/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]2.2 lb[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]5 mg[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center]22.7 kg[/TD]

[TD=align: center]x[/TD]

[TD=align: center]----[/TD]

[TD=align: center]=[/TD]

[TD=align: center]113.6 mg[/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]1.0 kg[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]1 mL[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[TR]

[TD=align: center]113.6 mg[/TD]

[TD=align: center]x[/TD]

[TD=align: center]----[/TD]

[TD=align: center]=[/TD]

[TD=align: center]0.9 mL[/TD]

[/TR]

[TR]

[TD=align: center][/TD]

[TD=align: center][/TD]

[TD=align: center]125 mg[/TD]

[TD=align: center][/TD]

[TD=align: center][/TD]

[/TR]

[/TABLE]

The answer for #1 is 1.3, not 1.5. The ordered dose was 0.325 not 0.375. Also, you have to divide #2 by 3, because it is supposed to be split into 3 equal doses, so the answer is 0.3.