The doctor has ordered an antibiotic whose average adult
dose is 250 mg per day. What would the dosage for this
medication be on a child who is 100 cm in length and weighs
25 kg? See the example below.
In this example, 117 mg of medication would
be given.
Formula
First, the body surface area (BSA)
must be determined:
kg0.425
x cm0.725 x 0.007184 = BSA
The above formula is just one
method for determining BSA. Results with other formulas
will vary.
Next, the following formula* is used:
BSA
x
adult dose = approx. child dose
1.73
*Gerald, M. C., & O’Bannon,
F. V. (1988). Nursing pharmacology and therapeutics. (2nd
ed.). Englewood Cliffs, NJ: Prentice Hall Incorporated.
Note: This web page is intended
for educational purposes. Do not use this tool for clinical
practice. This information is intended for nurses and nursing
students. Nurses are traditionally taught to use a nomogram
for estimating BSA. More accurate methods of pediatric dosing
exist. Only persons licensed in administering medications
may give medications. Also, not all drugs that are safe on
adults may be given to children due to differences in physiology.
Pets likewise do not share the same physiology as humans.
