Sig code: route
OU medical abbreviation
OU means "each eye", from the Latin "oculus uterque".
On the ISMP List of Error-Prone Abbreviations. ISMP suggests: Write "each eye".
Each meaning matched at least two public references (4 in all for OU), checked October 23, 2026. The table lists them.
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What OU means
| Meaning | Latin origin | Where used | Checked against |
|---|---|---|---|
| each eye | oculus uterque | Prescriptions, Medication labels |
Example
Training example of an error-prone entry: "OU" on an eye-drop label.
A made-up line that shows the abbreviation in place. It is not about any patient and is not an instruction.
Related abbreviations
Elsewhere on Rivvi
Questions
What does OU mean in medical terms?
OU means "each eye", from the Latin "oculus uterque".
What does OU stand for in Latin?
OU comes from "oculus uterque", meaning "each eye".
Where is OU used?
OU shows up in prescriptions and medication labels. Its category here is sig code: route.
Is OU on the Joint Commission Do Not Use list?
No, but ISMP lists OU as an error-prone abbreviation. ISMP's suggested practice: Write "each eye".