(4)
Work the following:
The normal adult dose of promethazine (Phenergan) is 25 mg. Using
the nomogram, calculate the dose for a 40-lb child having an average build for his
height.
ANS: ______ mg
(5)
Solution:
NOTE: The meter square reading may be taken from the center chart of the nomogram
if the child appears to be of average build.
The nomogram reading for a 40-lb child of average build is 0.75 M2.
NOTE: The meter square cancelled.
NOTE: The following formulas or rules are acceptable in pharmacy, but have a lesser
degree of accuracy than the Nomogram Method or the manufacturer's
recommended dosage. You should become familiar with each rule and be able
to use each if necessary.
b.
Fried's Rule:
Child's dose = Child's age in months X Adult dose
150 months
(2) Example problem: The adult dose of an antihistamine is 50 mg.
Calculate the dosage for a 2 -year-old child.
(3)
Solution:
30 months X 50 mg = 10 mg
150 months
MD0802
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