Pharmaceutical Abbreviations

Instructions

1. You should know and be able to use or interpret the BOLD FACED Latin abbreviations and their English meaning. The complete Latin equivalent is not required. This list has been selected from the typical Latin abbreviation listing and represents those abbreviations widely used in veterinary medicine.
2. You should know and be able to use the various terms for weights and measures for the Metric and Apothecaries' systems. For the Apothecaries' system, you need only know the term "grain" and the relationship between "fluid ounces" and "pint".
3. You should be able to interconvert between the systems, those relations that are printed below in bold typeface, using the approximate equivalencies. These conversions are commonly used in veterinary medicine and/or everyday living.

Latin Abbreviations

Abbreviation	Meaning	Latin
ad.lib.	freely as wanted	ad libitum
aq.	water	aqua
b.i.d.	twice a day	bis in die
cap.	capsule	capula
c with bar on top	with	cum
div.	divide	divide
eq.pts.	equal parts	equalis partis
gtt.	a drop	gutta
h.	hour	hora
no.	number	numero
O.	pint	octarius
p.r.n.	as occasion requires	pro re nata
q.s.	a sufficient quantity	quantum sufficiat
q4h	every 4 hours	quaque 4 hora
q6h	every 6 hours	quaque 6 hora
q1d	every day	quaque 1 die
q1w	every week
q.i.d.	four times a day	quater in die
s.i.d.	once a day	semel in die
Sig., S.	write on the label	signa
stat.	immediately	statim
tab.	a tablet	tabella
t.i.d.	three times a day	ter in die

Weights and measures used in prescribing and toxicology

The Metric System
Weight
1 picogram (pg)	10-12 gram
1000 picograms	1 nanogram (ng) or 10-9 gram
1000 nanograms	1 microgram (ug) or 10-6 gram
1000 micrograms	1 milligram (mg) or 10-3 gram
1000 milligrams	1 gram (g)
1000 grams	1 kilogram (kg)
Volume
1000 milliliters (ml)	1 liter (L)
Be able to interconvert all of these values Prefixes for volumes correspond to those for weight.

IMPORTANT: Know that 1 part per million (ppm) is a frequently used term in toxicology and drug residue discussions. For example, the following are 1 ppm: 1 mg / kg, 1 mcg/g. An analogy is "Percent" that represents 1 part per hundred, i.e., 1 g/100 g = 1% w/w. The expression "w/w" indicates that the amount of both substances is on a weight basis. It is assumed that ppm is w/w unless otherwise specified.

The Apothecaries' System
Weight
20 grains (gr)	1 scruple ( )
3 scruples	1 dram( ) = 60 grains
8 drams	1 ounce ( ) = 480 grains
Volume
60 minims (m)	1 fluid dram ( )
8 fluid drams	1 fluid ounce ( )
16 fluid ounces	1 pint (O.)
Know eqivalents in bold faced typed

Conversion Equivalents

	Approximate	Exact
1 milligram	1/60 grain	1/65 grain
1 gram	15 grains	15.432 grains
1 kilogram	2.2 pounds*	2.2 pounds*
1 milliliter	15 minims	16.23 minims
1 liter	1 quart	1.06 quarts or 33.8 fluid ounces
1 grain	60 milligrams	65 milligrams
1 dram	4 grams	3.88 grams
1 ounce	30 grams	31.1 grams
1 pound*	450 grams	454 grams
1 minim	0.06 milliliter	0.062 milliliter
1 fluid dram	4 milliliters	3.7 milliliters
1 fluid ounce	30 milliliters	29.57 milliliters
1 pint	500 milliliters	473 milliliters
1 quart	1000 milliters	946 milliliters
1 drop	1 minim
1 teaspoonful	5 milliliters
1 dessertspoonful	8 milliliters
1 tablespoonful	15 milliliters
Know equivalents in bold faced type. Note: Where possible, use suitable units rather than decimal fractions, e.g., 10 mg not 0.010 g. When a decimal fraction is used the decimal point must be preceded by a zero, e.g., 0.5 not .5. * = avoirdupois pound (the one used in the USA!)

Conversion factors for obtaining approximate equivalents

To convert	To	Multiply by
gr/lb	mg/lb	60
gr/lb	mg/kg	143
mg/lb	gr/lb	0.015
mg/lb	mg/kg	2.2
mg/kg	gr/lb	0.007
mg/kg	mg/lb	0.45
Know conversions in bold typeface