question with a daosage problem

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Specializes in med-surg.

Hello Everyone,

I just started pharmacology class and was stumped with one problem. The answer I got doesn't match with the answer in the book. I am sure it is something simple and I am missing it. Please can you help me figure this out?

Physician has ordered acyclovir, 1200mg, IV, each day, in 3 divided doses q 8 hrs. Dosage instructions on the vial are 15mg/kg per day. Diluted concentrate will be 50mg/mL. Dilute further for IV to 7mg/mL. The patient weighs 176lbs.

How many mL of drug concentrate must be added to a 100mL bag of IV fluid to meet the dose ordered?

I calculated the mg dose for the patient, which is 1200mg and could not go further.

I would appreciate the help. Thanks!

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unless the question is asking "is this a safe dose for this patient" you dont need the wt or mg/kg....divide 1200 by 3=400, divide that by 50= 8, which is the #of ml of concentrate required

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Specializes in med-surg.
unless the question is asking "is this a safe dose for this patient" you dont need the wt or mg/kg....divide 1200 by 3=400, divide that by 50= 8, which is the #of ml of concentrate required

Thanks a lot for your help. I am sorry I didn't mention it, but the next question did ask:

Is this diluted strength of the drug in the IV fluid 7mg/mL or less? and

What is the diluted strength of the drug in the IV fluids?

The answer in the book says 4mL of concentrate and that's what confused me.

Can you please clarify? Thanks!

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Specializes in med/surg, telemetry, IV therapy, mgmt.
Physician has ordered acyclovir, 1200mg, IV, each day, in 3 divided doses q 8 hrs. Dosage instructions on the vial are 15mg/kg per day. Diluted concentrate will be 50mg/mL. Dilute further for IV to 7mg/mL. The patient weighs 176lbs.

How many mL of drug concentrate must be added to a 100mL bag of IV fluid to meet the dose ordered?

400mg (dose desired)/7mg (dose on hand) x 1 mL (amount the 7mg is in = 57.1428, rounded off to 57 mL (amount of drug concentrate to add to the 100 mL bag of IV fluid)

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Specializes in med-surg.
400mg (dose desired)/7mg (dose on hand) x 1 mL (amount the 7mg is in = 57.1428, rounded off to 57 mL (amount of drug concentrate to add to the 100 mL bag of IV fluid)

Daytonite,

thanks a lot for the help!

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