What do AC and PC mean on a prescription?
AC means before meals and PC means after meals.
What it stands for
AC and PC comes from the Latin ante cibum and post cibum, meaning before food and after food. It tells you the timing of the dose relative to eating.
How it looks on a real label
| Sig code | Label directions |
|---|---|
1 cap po bid ac | Take 1 capsule by mouth twice daily before meals |
2 tabs po tid pc | Take 2 tablets by mouth three times daily after meals |
1 cap po qid ac | Take 1 capsule by mouth four times daily before meals |
Food timing is on the label because it changes how the medication behaves. Some are absorbed poorly with food in the stomach, which is why they are dosed AC. Others irritate the stomach lining and are dosed PC to blunt that.
A patient who takes a PC medication on an empty stomach usually just feels unwell. One who takes an AC medication with a meal may get less benefit than expected, which is harder to notice.
Related codes
| Code | Meaning |
|---|---|
HS | at bedtime |
QAM | every morning |
PO TID | by mouth three times daily |
PRN | as needed |
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This page is educational and is not medical advice. Always follow the directions on your own prescription and ask your pharmacist if anything is unclear.