alt
alternating
b.i.d.
Twice a day
b.i.w.
Twice a week
HS
At bedtime
OD or od
Once a day / Daily
q
Every
q8h
Every 8 hours
q6h
Every 6 hours
q12h
Every 12 hours
q.i.d.
Four times a day
q.o.d.
Every other day
t.i.d.
Three times a day
t.i.w.
Three times a week
h
hour