Pharmacy reference

Pharmacy SIG codes and abbreviations

Find a term, read its meaning, and keep the ambiguity check beside it.

Recognition aid, not a prescription translator. Confirm the complete directions and clarify ambiguous instructions before making a patient label.

OD

Right eye or once daily

Ambiguous across contexts. Clarify rather than selecting a meaning automatically.

ISMP safety reference

OS / OU

Left eye / each eye

Write the eye explicitly; eye and ear abbreviations can be confused.

ISMP safety reference

.5 / 5.0

Decimal notation

Write 0.5 for a fraction; avoid a trailing zero in a medication dose.

ISMP safety reference

Use your browser’s Print command to save or print this list. Clear the search first for the full reference, or print the filtered entries you need. Keep the caution notes with the meanings.

Read the whole instruction

A recognized abbreviation cannot supply an omitted dose, route, duration, treatment site or as-needed limit. Write clear patient-facing directions after verifying the intended instruction. Keep the original prescription and any clarification available in the pharmacy record.

The MedlinePlus abbreviation appendix is a general recognition reference. The 2024 ISMP list addresses reported medication-communication hazards; it is broader than this selected glossary.

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Look up selected frequency, route and dose terms. Ambiguous directions need clarification, not a guessed translation.