What per os stands for

per os is a medical abbreviation for by mouth - written out in full as “Per os (by mouth)”. TermDecode files it under route abbreviations.

RouteFlagged high riskSourced

Risk

Can be mistaken for "OS" (left eye)

Safer Alternative

Write "PO", "by mouth", or "orally"

Seen in context

per os misread as left eye

Sources

The risk description and safer alternative above are reproduced from these published lists.

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Other route abbreviations