question about ml/hr

by Sheila
(Dunwoody,GA)

Here is my problem:

The initial dose of Rebif is 0.7mg/kg/hr for 12 hours. How many ml of Rebif IV solution containing 400mg/ml would be needed for an adult male weighing 154 lbs during this 12 hour period?

I think this a ml/hr problem. First I converted 154 lbs to 70 kg and multiplied by the 12 hours. I get 588 mg. I divided the 588 by 400 and get 1.47. Is this correct? The answer provided is 147 ml. I think I am missing a step.

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question about ml/hr

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Mar 09, 2012
Pharmacy Calculations and Measurments Systems
by: Anonymous

I'm having trouble solving this problem. Could you show me how to solve this problem step-by-step?

Calculate the dosage and mL/hr flow rate for the following drug. Propofol 5mcg/kg/min is ordered for an 80.3 kg patient. The solution strength is 1 g/100mL D5W.


Feb 10, 2012
plugg in
by: Anonymous

mg/kg/hr

0.7mg/70kg (154 / 2.2)/12hrs= 588
take that n divide by 400mg
you get 1.47

Feb 09, 2012
IV drug calculation
by: ellen

pts dobutamine drip is infusing at 25cc/hr.his weight is 79kg.the medication is premixed 800mg in 250cc d5w. How many mcg/kg/min is this patient recieving?

Oct 11, 2011
Just giving this try.
by: Jay

1)The order is for 0.7mg/kg/hr for 12 hours.

2)What's in the I.v bag is Rebif IV solution containing 400mg/ml.

(I came up with the answer of 0.1)

I converted 154lbs to 70kg.
5ml/400mg = 0.0125 * 0.7 = 0.00875 * 12 = 0.105

Jul 15, 2011
THE ANSWER IS CORRECT
by: FROZEN FOREVER

CONVERT 1bs TO KG

154 lbs =70KG

NOW MULTIPLY .7KG *70MG AND YOU GET 49MG/KG

NOW DIVIDE 49MG BY 400MG AND YOU GET.1225ML

FOR 12 HRS MULTIPLY .1225 BY 12 AND YOU GET 1.47ML

Jul 14, 2011
1.47ml is correct
by: KTN315

Dose: 0.7mg/kg/hr.
Pt's wt: 154 lbs.

Convert his weight to kg.
(154/2.2) = 70kg

Now calculate the milligrams needed per hour.
0.7mg * 70kg = 49mg

You know that he's using it for 12 hours.
49mg * 12 hrs = 588mg.

The available size is 400mg/ml.
400mg 588mg
----- = ----- = (588*1)/400 = 1.47ml
1 ml ?

May 28, 2011
Rebif dosage
by: Craig

Apparently the 1.47 answer is correct. According to Mfg. dosage for Rebif-44 mcg SC 3 times week. Start: 8.8 mcg 3x/wk x 2wk, then 22 mcg SC 3x/wk x 2 wk; give doses 48h apart. obviously very concentrated. Note mcg not mg.

Apr 14, 2011
1.47mL is correct
by: Laura

I've done the problem and also come up with 1.47mL. I think the answer key in your book is erroneous. The solution is highly concentrated at 400mg/mL, so the answer being given as 147mL in your book is incorrect (that would calculate out to 58.8 GRAMS of the medication, which is probably lethal :/). I believe they forgot the decimal. What book are you using? I've found errors in my study guide, as well.

Apr 05, 2011
the answer is correct
by: Anonymous

I just did the problem myself. 1.47mL is the needed amount for that patient.

Mar 30, 2011
Looks like you are correct
by: Anonymous

(0.7)*(70)*(12) = 588

So, 588mg is the total needed

1mL of the provided solution has 400mg

400mg - - 588mg
----- - = - -------
1mL - - (X)

x = 1.47mL

Mar 30, 2011
Still do not have a complete answer
by: Sheila

Both Barb and I are confused over the 1.47 ml answer. Would someone please verify?

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