1. Pharmacy Units Measurements and Abbreviations
There are others in the Student Handout book
The most common ones (Must know)
C=Celsius
F =Fahrenheit
G or gr =Gram
Gr. = grain
L= liter
Ml= Milliliter
Mg=Milligram
Kg=Kilogram
TBSP= tablespoon
TSP= Teaspoon
Gtt= drop

2. Measurement Systems Metric System- began in France in 1795.
Denotes basic units of measurement in 6 main areas:
Mass - Gram
Length- meter
Time- second
Volume- liter

3. Metric System is the preferred system in science and medicine due to its factor of ten basis. Used in most countries in the world
Prefix and meaning
Pico= (trillionth)
Nano = (billionth)
Micro = (millionth)
Milli =0.001 (thousandth)
Centi=0.01 (hundredth)
Deci = 0.1 (tenth)
Kilo=1,000 (thousand)

4. Visual method to conversion between Metric units
Number Line System
To convert metric system units, plot your two units on the number line from left to right; if the conversion makes you move to the right you will move the decimal point the same number of place as you have zero’s
If the conversion makes you move to the left you move the decimal to the right the same number of place that you make zero’s
1000 X
1000 X
1000 X
Milli
Micro
Base Unit
kilo

5. Visual method to conversion between Metric units
For example
To convert 200 mcg to mg, plot it on the number line:
to get there you must move to the right of the number line thus you move the decimel to the left the same number of units that there are zeros in the convert (i.e.3)
200 mcg= mg or just 0.2 mg
1000 X
1000 X
1000 X
To Here
Here
Milli
Micro
Base Unit
kilo

6. US Customary Units and British Imperial Systems
Development over centuries in the British Isles and later in the US colonies
Formally standardized in 1824
Still use in the US and Great Britain Today; however, almost all scientific applications use the metric system or the SI system (Système international d'unités )
Avoirdupois system is a subsystem of weights in the US and British Systems based on the pound.

7. Avoirdupois System Weight Volume 20 grains= 1 scruple
3 scruples= 1 dram
8 drams = 1 ounce ***
16 ounces = 1 lbs ***
Volume
60 minims= 1 fluid dram
8 fluid drams = 1 fluid ounce ***
16 fluid ounces = 1 pint ***
2 pints= 1 quart ***
4 quarts = 1 gallon ***

8. The follow is a list of weights and their metric equivalents
1 Grain = 65 mg (5 gr aspirin =325 mg)
exception: 1 gr of thyroid, phenobarbital, codeine and nitroglycerin) is 60 mg
1 lb (pound) = 16 ounces
1 ounce = grams
1 fl. Oz= ml (remember 30 ml)
2.2 pound = 1 kilograms ***
1 Dram (symbolized by ʒ) = 3.9 g
1 f ʒ = 3.9 ml
1 pint = 473 ml

9. Household measurements
1 tsp = 5 ml
1 tbsp= 15 ml
1 cup = 8 ounces or 240 ml
20 gtts = 1 ml (use to calculate the number of drops in eye drop products )
20 drops/ 1 ml = x drops/ 5 ml
X= 20 X5
X= 100 drops
5 ml is how many drops?

10. Apothecary System
Apothecary system is a system of weights and measure used in Europe during the 18th century by physicians and pharmacist (apothecary)
Is a subset of the British Imperial systems
The following is important to remember in pharmacy
The only difference between apothecary system and Avoirdupois system is the troy ounce is heavier than the avoirdupois ounce. the troy ounce which is the 31.1 grams instead of grams
Precious metals and gemstones are weighted in troy ounces. Gold=Au, Silver= Ag, Platinum = Pt