Question: A physician prescribes codeine 30mg, q4h prn, for a child in pain. The child weighs 45 lbs. The safe dosage is 5 - 10 mg/kg/dose. If the nurse gave 30 mg/dose, six times a day, would this be a safe dose?
I worked the problem this way:
Convert the child's weight to kg: 45 pds divided by 2.2kg = 20.5kg
Calculate the safe dose based on child's weight: 20.5kg x 5mg/kg = 102.3mg
20.5kg x 10mg/kg = 204.5mg
Desired safe dosage is 102.3mg - 204.5mg
Now, answer the question, if the nurse gave 30mg/dose, six times a day, would this be a safe dose? 30mg x 6 times a day = 180mg.
The answer is Yes, 30mg q4h (or 6 times per day) is a safe dosage because 180mg falls between the min (102.3mg) and the max (204.5mg).
Do you agree?
Oct 15, '13
Here is the deal....your calculations for the problem are correct.
However....the dosage 5-10mg/kg per dose is too high. The dosage for children is 0.5 to 1 mg/kg administered every 4 to 6 hours as needed, to a maximum of 60 mg/dose.
https://online.epocrates.com/u/10212...diatric+Dosing
[3-6 yo]Dose: 12 mg codeine PO q4-6h prn; Max: 60 mg/dose codeine; Alt: 0.5-1 mg/kg codeine PO q4-6h prn; Info: do not exceed 75 mg/kg/day up to 1 g/4h and 4 g/day acetaminophen, 360 mg/day codeine from all sources; give w/ food; elixir contains 7% alcohol; taper dose gradually to D/C if long-term use
[7-12 yo]Dose: 15-30 mg codeine PO q4-6h prn; Max: 60 mg/dose codeine; Alt: 0.5-1 mg/kg codeine PO q4-6h prn; Info: do not exceed 75 mg/kg/day up to 1 g/4h and 4 g/day acetaminophen, 360 mg/day codeine from all sources; give w/ food; elixir contains 7% alcohol; taper dose gradually to D/C if long-term use
[13-17 yo]Dose: 15-60 mg codeine PO q4-6h prn; Max: 60 mg/dose codeine; Alt: 0.5-1 mg/kg codeine PO q4-6h prn; Info: do not exceed 75 mg/kg/day up to 1 g/4h and 4 g/day acetaminophen, 360 mg/day codeine from all sources; give w/ food; elixir contains 7% alcohol; taper dose gradually to D/C if long-term use
Does the question really state.....per dose??
The safe dosage is 5 - 10 mg/kg/dose
Last edit by Esme12 on Oct 15, '13
Nov 24, '13
Would it matter that it's a child for a more accurate dose? I was taught that peds patients have to be exact. Meaning the kgs would be rounded to the hundreth not the tenth. In this case it would be 20.45 kgs. I'm asking in case you are graded for showing your work.
Either way according to that problem the answer is yes. In the real world? No. I have seen some outrageous math questions in class that make no sense in the real world. The thing with the class work is that they just want to see if you can answer the questions correctly so don't worry about the minute detail that it's not realistic and only worry about finding the correct answer.
Edit: I do see after rereading the problem that it says safe dosage range is 5-10mg/kg/DOSE by your calculations you answered if 30mg q4h exceeds the DAILY limit not the dosage limit... You may want to clarify that because while it's a safe dose anyways, 102.3mg-204.5mg/DOSE is far far more than 30mg/DOSE. Those little things will hurt your calculations if you don't pay attention to them.
Last edit by quirkystudent on Nov 24, '13