Common sig codes (directions)

Claim

Sig abbreviations encode directions (e.g., BID twice daily, TID three times daily, QHS at bedtime, PRN as needed, PO by mouth). Prefer clear language on labels; treat ambiguous or error-prone abbreviations as a safety risk and expand them.

Plain

BID=2×/day, TID=3×/day, QHS=at bedtime, PRN=as needed, PO=by mouth. When unclear, expand — don’t guess.

Citations

1. PTCB PTCE Content Outline (2026) — Order Entry & Processing (Order Entry & Processing — sig / directions) — source
   

   [Domain pin — verify exact wording in the current PTCB PTCE Content Outline PDF before paste.] Order Entry & Processing — sig / directions

   retrieved 2026-09-07
2. ISMP — List of Error-Prone Abbreviations (ISMP error-prone abbreviations (safety context)) — source
   

   ISMP publishes a List of Error-Prone Abbreviations, Symbols, and Dose Designations that should not be used in medication communications.

   retrieved 2026-09-07