B.PHARMACY I-SEM PHARMACEUTICS.

1. PHARMACEUTICAL
CALCULATION

2. INTRODUCTION
• Pharmacist should know the complete understanding
of various types of calculations, which are involved
in dispensing.
• The pharmacist should have thorough knowledge
regarding weights and measures because which are
extensively used in the pharmaceutical field.
• There are three systems of weight and measures,
1. The imperial system
a) Avoirdupois system
b) Apothecaries system
2. The metric system
3. The household system

3. IMPERIAL SYSTEM
This system is an old system of weight and measures
WEIGHTS
1. Avoirdupois system
 Pound (lb) - standard unit for weighing
2. Apothecaries system
 Troy system.
 Grains (gr) - standard unit for weighing
CONVERSION
1 pound - 16 ounce
1 pound - 700 grains
1 ounce - 437.5 grains
20 grains - 1 scruple
60 grains - 1 drachm
80 grains - 1 ounce
12 ounce - 1 pound
5760 grains - 1 pound

4. CAPACITY:
 Gallon – standard unit for both avoirdupois and apothecaries
system.
CONVERSION:
gallon – 160 fluid ounce
1/4 th gallon – 1 quart
1/8 th gallon – 1 pint
1/160 th gallon – 1 flounce
1 quart – 40 flounces
1 pint – 20 flounces
1 flounce – 480 minims
1 fluid drachm – 60 minims

5. METRIC SYSTEM
 Metric system is used in Indian pharmacopoeia for the measurement of
weights and capacity.
 It was implemented in India from 1st April, 1964 in pharmacy
profession.
 Kilogram – standard unit for weight
 Litre – standard unit for capacity
1 kilogram – 1000grams
1 hectogram – 100grams
1 decagram – 10 grams
1 decigram – 0.1 gram
1 centigram – 0.01 grams
1 milligram – 0.001 grams
1 microgram – 0.000001 gram
1 litre – 1000 millilitre

6. CONVERSION TABLE
 IP – only metric system
 Till some prescription written in imperial system.
WEIGHT:
Metric system Imperial system
1 kilogram 2.2 pound (lb)
30gm 1 ounce
450gm 1 pound
1 gram 15 grains
60mg 1 grains
CAPACITY:
Metric system Imperial system
100ml 1 quart
500ml 1 pint
30ml 1 fluid ounce
5 ml 1 fluid drachm
1ml 15minims
0.06ml 1 minim

7. Household system
Household measure Metric system Imperial system
1 drop 0.06ml 1 minim
1 teaspoonful 5ml 1 fluid drachm
1 dessertspoonful 10ml 2 fluid drachm
1 tablespoonful 15ml 3 fluid drachm
2 table spoonful 30ml 1 fluid ounce
1 wine glassful 60ml 2 fluid ounce
1 teacupful 120ml 4 fluid ounce
1 tumbler 240ml 8 fluid ounce
1 pint 480ml 16 fluid ounce
1 quart 960ml 2 pint
1 gallon 3840ml 4 quart

8. THANK YOU