a, pre
before
ac
before meals
ad lib
at pleasure, freely
am
morning, before noon
ATC
around the clock
bid
twice a day, twice daily
h, hr
hour
hs
at bedtime
MR, mr
may repeat, may refill
noc
at night
p, post
after
pc, pp
after meals
post-op
post operative, after surgery
prn
as needed
q
every
qd
every day
qh
every hour
q3h
every three hours
qid
four times a day, four times daily
qod
every other day
RX, Rx
take thou
Sig, sig
let it be written, directions, label
tid
three times a day, three times daily
tiw
three times a week
ud
as directed
wk
week