OS
left eye
OD
right eye
OU
both eyes
AS
left ear
AD
right ear
AU
both ears
SID
once daily
BID
twice daily
TID
three times daily
QID
four times daily
q12hr
every 12 hrs
ad lib
as much as desired
cap
capsule
d
day
dr
dram (4ml)
gm or g
gram
gt
drop
gtt
drops
non rep
do not repeat
NPO
nothing per mouth
per os
by mouth
PO
by mouth
prn
as needed
q
every