Page 18 - A Guide to Dosage Form 1

Units are very important in pharmaceutical formulation because it involves many different
measurements and measuring equipments. Hence, a pharmacist should be able to understand,
familiarize and perform unit conversions, and to do it precisely. Inability to do so may be an inadequacy
for a pharmacist to practice, and a careless mistake may cause adverse effect on patients’ well-being.
Therefore, care must be in place when calculating doses and measuring ingredients for formulations.

METRIC UNITS

METRIC UNIT FOR LENGTH
2
1 m = 100 cm = 10 cm
3
= 1000 mm = 10 mm

6
= 10 µm
9
= 10 nm
1 mm = 1000 µm = 10 µm
3

3
1 µm = 1000 nm = 10 nm

METRIC UNIT FOR MASS
1 kg = 1000 g = 10 g
3
1 g = 10 kg
-3
3
= 1000 mg = 10 mg
6
= 10 µg
= 10 ng
9
3
1 mg = 1000 µg = 10 µg
3
1 µg = 1000 ng = 10 ng

METRIC UNIT FOR VOLUME
1 L = 1000 mL = 10 mL
3
= 10 cc
3
6
= 10 µL
3
1 mL = 1000 µL = 10 µL
= 1 cc = 10 mg
3

US MEASURES (VOLUME)

VOLUME MEASURES
1 fluid ounce (fl oz) = 29.57 mL

1 pint (liq pt) = 473 mL