What does PO TID mean on a prescription?
PO TID means take the medication by mouth three times daily.
What it stands for
PO TID comes from the Latin ter in die, meaning three times a day. It tells you the frequency: three doses spread across the waking day.
How it looks on a real label
| Sig code | Label directions |
|---|---|
1 tab po tid | Take 1 tablet by mouth three times daily |
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 |
PO TID is not the same as Q8H
TID means three times a day, which in practice usually means with meals: morning, midday and evening. The patient has some flexibility, and nobody wakes up for a dose.
Q8H means every 8 hours on a strict clock, which does include overnight. Three doses either way, but Q8H spreads them evenly and TID does not.
For an antibiotic where a steady blood level matters, that difference is the point. If a prescriber writes Q8H rather than TID, they usually mean it.
Related codes
| Code | Meaning |
|---|---|
PO BID | by mouth twice daily |
PO QID | by mouth four times daily |
PO QD | by mouth once daily |
Q8H | every 8 hours |
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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.