B.i.d
Twice a day/daily
Gtt.
Drop
H.
Hour
H.s
At bedtime
P.c
After food
Po
Orally
P.r.n
As needed
Q.
Every
Q.2.h.
Every two hours
Q.4.h
Every four hours
Q.6.h
Every six hours
Q.8.h
Every eight hours
Q.h
Every hour/hourly
Q.i.d
Four times a day
Q.s
A sufficient quantity
Rex
Prescription
Sig or S.
Directions
Stat.
Immediately with no delay
T.i.d
Three times a day
U.d
As directed
IV
Intravenously
SC
Subcutaneous
SL
Sublingual
IM
Intramuscular