dosage calculation problem

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Specializes in NICU.

I'm confused on this particular problem. Can someone please explain how you would solve this? Thank you!

250mg of Ceptaz must be prepared. The drug its available in a powdered drug containing 1g. Directions are to add 10mL solution to yield 90mg in 1mL. How many mL should you administer?

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Specializes in Adult Internal Medicine.

Are you sure the question says 90mg per 1mL? If you dilute 1g with 10mL what do you get for a concentration?

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Specializes in NICU.

Thats exactly how the question is worded on the practice problem. I'm not really sure the whole question has me confused

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Specializes in NICU.

I think I figured it out, I set up the ratio 90mg/1mL=250mg/xmL and got x=2.77, the answer key said 2.8

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Specializes in Adult Internal Medicine.
I think I figured it out I set up the ratio 90mg/1mL=250mg/xmL and got x=2.77, the answer key said 2.8[/quote']

If you assume a concentration of 90mg/mL that's absolutely correct.

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Specializes in NICU.

Thank you! I got one more for you...

3/4 strength Osmolite must be prepared. Available is full strength. To prepare 175mL of feeding, how much Osmolite should be mixed with how much water?

No idea how to set that up :/

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Thank you! I got one more for you... 3/4 strength Osmolite must be prepared. Available is full strength. To prepare 175mL of feeding how much Osmolite should be mixed with how much water? No idea how to set that up :/[/quote']

There's not enough info to set it up. How many mL is full strength?

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Specializes in NICU.

Thats what I was thinking but it doesn't say? There were several questions like that on the practice sheet

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Specializes in Pedi.
There's not enough info to set it up. How many mL is full strength?

Sure it's enough info. You need to administer 175 mL. 3 parts of it need to be formula and 1 part of it needs to be water.

"Full strength" is 100% formula. That's all you need to know. If you administer 175 mL of straight Osmolite that's a full strength feeding. If you administer 350 mL of straight Osmolite, that's also a full strength feeding. If you dilute it to a concentration of 50% osmolite/50% water, that's half strength. This question is simply asking you to multiply.

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Sure it's enough info. You need to administer 175 mL. 3 parts of it need to be formula and 1 part of it needs to be water. "Full strength" is 100% formula. That's all you need to know. If you administer 175 mL of straight Osmolite that's a full strength feeding. If you administer 350 mL of straight Osmolite that's also a full strength feeding. If you dilute it to a concentration of 50% osmolite/50% water, that's half strength. This question is simply asking you to multiply.[/quote']

Mm. Nope. Never had a question like that in math dosage or math test. Can't help there.

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Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
Sure it's enough info. You need to administer 175 mL. 3 parts of it need to be formula and 1 part of it needs to be water.

"Full strength" is 100% formula. That's all you need to know. If you administer 175 mL of straight Osmolite that's a full strength feeding. If you administer 350 mL of straight Osmolite, that's also a full strength feeding. If you dilute it to a concentration of 50% osmolite/50% water, that's half strength. This question is simply asking you to multiply.

absolutely correct :)

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Specializes in Pedi.
Mm. Nope. Never had a question like that in math dosage or math test. Can't help there.

Whether you've had a question like this or not, there's still enough info in the problem to figure out the answer. If you know fractions, you can do this problem.

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