Medication  Metric Conversions
Metric units and conversions for the calculation and administration of medication.
Basic Metric Units for drug administration
Quantity 
Unit 
Symbol 
length 
metre 
m 
mass 
gram 
g 
volume 
litre 
l 
time 
second 
s 
Common Units of Measurement for drug administration
The various quantities of these units often have a prefix to make writing quantities more succinct. For example 0.000001g may be written as 1 mcg (or 1µg.)
Prefix 
Symbol 
Multiplication factor 
mega 
M 
1,000,000 
kilo 
k 
1,000 
hecto 
h 
100 
deka 
da 
10 
unit 
e.g. g, m, l or s 
1 
deci 
d 
0.1 
centi 
c 
0.01 
milli 
m 
0.001 
micro 
mcg or µ 
0.000001 
Converting a number from one metric unit to another involves moving the decimal place to the left or the right. To work out how many decimal places to move:
 Identify the metric scale
 Identify the two units in the problem
 Count the number of units from the current unit to the desired unit
 Move the decimal point the number of places from the given unit to the desired unit
Example 1  Convert 0.1 grams to milligrams.
The decimal point is moved 3 places to the right  0.1 g = 100 mg
Example 2  Convert 375 millilitres to litres.
The decimal point is moved 3 places to the left  375 ml = 0.375 l
