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 |
Weights
and measures
used in prescribing
and toxicology
| Weight |
The
Metric
System |
| 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) |
| 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.) |
| 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 |