Here are the common (and some not-so-common) abbreviations used when writing a prescription. Several apothecary symbols have been omitted because I have no way of representing them, but they are rarely, if ever, used. Please /msg me if I've made any mistakes or glaring omissions.
ac before meals ("ante cibum") NS normal saline, 0.9%
ad right ear 1/2NS half normal saline, 0.45%
ad lib use as you wish ("ad libitum") od right eye
am morning os left eye
amp ampule ou both eyes
aq water per by or through
as left ear pc after meals ("post cibum")
au both ears pm evening
bid twice daily po by mouth ("per os")
BSA body surface area prn as needed ("pro re nata")
cap capsule q each, every ("quaque")
cc milliliter (cubic centimeter) qd every day ("quaque die")
D/C discontinue qh every hour
da, daw dispense as written q_h every _ hours
dil dilute qid four times a day
DW distilled water qod every other day
D5W 5% dextrose in water qs a sufficient quantity
elix elixir R by rectum, rectal
fl fluid RL Ringer's lactate
g gram sig write on label
gr grain sol solution
gtt drop(s) ("guttae") stat stat
h, hr hour SC subcutaneous
hs bedtime supp suppository
IM intramuscular susp suspension
IV intravenous syr syrup
IVP intravenous push tab tablet
IVPB intravenous piggyback tbsp tablespoonful
mcg microgram tsp teaspoonful
mEq milliequivalent tid three times a day ("ter in die")
mg milligram ud as directed
mL milliliter ung ointment
N/V nausea and vomiting ut dict as directed ("ut dictum")
noct at night
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