Abbreviations
Frequency of Intake
Intake Period
More Intake Periods
100

Immediately or at once

What is STAT.?

100

Every 2 hours

What is Q2H?

100

Every morning

What is QAM?

100

Twice a day

What is B.I.D?

200

Around the clock

What is A.T.C?

200

Every 6 hours. 

What is Q6H?

200

At bedtime; as in "hour of sleep."

What is H.S?
200

Four times a day

What is QID (q.i.d.)?

300

As desired.

What is Ad. Lib.?

300

Every 12 hours.

What is Q12H?

300

Every night at bedtime

What is QHS?

300
Once Every Week

What is QWK

400

As directed; as in Ut dictum.

What is UD?

400

Every 24 hours


What is Q24H?

400
Before Every Meal

What is QAC?

400

Twice a week (often Monday/Thursday or similar)

What is BIM?

500

Use as needed; as in Pro re nata...

What is P.R.N?

500

Every 72hrs; as in every 3 days. 

What is Q72H?

500

After meals

What is P.C?

500

Weekly; as in once a week.

What is QWK

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