a = before
A.C. = before meals
ad = to; up to
ad lib = freely
B.I.D. = twice a day
b.i.w. = twice a week
c. = with
C. = centigrade
cc. = cubic centimeter
cm. = centimeter
cap. = capsule
EEG = electroencephalogram
EKG = electrocardiogram
elix. = elixir; drugs dissolved in syrup containing alcohol
F. = Fahrenheit
G.A.D. = glucose, acetone and diacetic acid urine test
G.I. = gastrointestinal
Gm. = gram
Gm./100 ml. = grams per 100 milliliters
gr. = grain
gtt. = drops
H.S. = at bedtime (hour of sleep)
i = One (1)
I.M. = intramuscularly
I.V. = intravenously
Kg. = kilogram
L. = liter
lb. = pound
L./min. = liters per minute
mg. = milliliter
N.P.O. = nothing by mouth
O = a pint
o.d. = every day
o.m. = every morning
o.n. = every night
oz. = ounce
P.C. = after meals
per = by or through
pH = measure of alkalinity and acidity
p.o. = postoperative
P.O. = by mouth
P.R. = by rectum
p.r.n. = whenever required
q. 2(3,4) h. = every 2(3,4) hours
Q.D. = every day
q.H. or q. 1H. = every hour
Q.I.D. or 4 i.d. = four times a day
Q.O.D. = every other day
q.s. = a sufficient quantity
qt. = quart
s = without
sig = label
sol = solution
S.O.S. or s.o.s. = if necessary
Stat = immediately; at once
T = One
tab = tablet
tbsp. = tablespoon
T.I.D. = three times a day
tsp. = teaspoon
ung = ointment
U.R.I. = upper respiratory infection
vol.% = volume per cent

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