# Need help with Dosage cal.

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I need help with a dosage problem, can't figure out how to set it up:( Math is NOT my favorite subject lol. Ok here is the problem: 0.2 mg/kg is ordered, 20 mg/ml available in 30/ml bottle with measured dropper. Can anyone clue me in as to how to set up the problem?

How many kg does the pt weigh?

I need help with a dosage problem, can't figure out how to set it up:( Math is NOT my favorite subject lol. Ok here is the problem: 0.2 mg/kg is ordered, 20 mg/ml available in 30/ml bottle with measured dropper. Can anyone clue me in as to how to set up the problem?

Suppose the patient weighs 150lbs..

Divide by 2.2lbs/kg to get the weight in kg:

(150lbs/(2.2lbs/kg)) = 68.2kg

Set up a ratio with the given order to find the dosage:

(0.2mg/kg) = (Xmg/68.2kg) Solve for X and you'll get 13.64mg

Now set up another ratio with the available medication to find the ml/dose:

(20mg/ml) = (13.64mg/Xml) Solve for X and you'll get 0.68ml

So this patient weighing 150lbs would require a dose of 0.68ml

Thanks! forgot about figuring the weight of the patient....feeling the stress! end of semester is almost here....and not sure if I will make the cut or not:(