Abbreviations
Veterinary Prescription Abbreviations: SID, BID, TID, QID, PO, SC, IM, IV and More
Abbreviations for dosing frequency, routes of administration and the eye or ear to treat, as defined in the University of Michigan list of accepted veterinary shorthand [2] and the University of Illinois Veterinary Medicine Library guide [1]. Abbreviations that the Institute for Safe Medication Practices lists as error-prone are flagged with its recommended wording [4].
Prescription and route abbreviations (31)
| Abbreviation | Meaning | Caution |
|---|---|---|
| SID | Once per day [2] | |
| BID / b.i.d. | Twice a day — Latin bis in die [1][2] | |
| TID / t.i.d. | Three times a day — Latin ter in die [1][2] | |
| QID / q.i.d. | Four times a day — Latin quater in die [1][2] | |
| q | Every, each — Latin quaque; e.g. qh every hour, q4h every four hours [1][2] | |
| q.d. | Every day — Latin quaque die [1] | ISMP: mistaken as q.i.d.; write "daily" [4]. |
| EOD / qod | Every other day [1][2] | ISMP: qod is mistaken as qd (daily) or qid (four times daily); write "every other day" [4]. |
| PRN | As needed — Latin pro re nata [1][2] | |
| ad lib | Ad libitum, as much as desired [1]; available at all times [2] | |
| pc | After meals — Latin post cibum / cibos [1] | |
| NPO | Nothing by mouth — Latin nil per os [1][2] | |
| PO | By mouth — Latin per os [1][2] | |
| SC / SQ | Subcutaneous(ly) [1][2] | ISMP: SC is mistaken as SL (sublingual), SQ as "5 every", and the q in sub q as "every"; write SUBQ (capitals, no spaces or periods) or subcutaneous(ly) [4]. |
| IM | Intramuscular [1][2] | |
| IV | Intravenous [1][2] | |
| IP | Intraperitoneal [1][2] | |
| ID | Intradermal [1][2] | |
| IN | Intranasal [1][2] | ISMP: mistaken as IM or IV; write "intranasal" [4]. |
| IC | Intracardiac [1][2] | Also infectious coryza in poultry [1]. |
| CRI | Constant-rate infusion [3] | |
| NSAID | Nonsteroidal anti-inflammatory drug(s) [1][3] | |
| OTC | Over the counter [3] | |
| Rx | Latin recipe, take — used to indicate a prescription or treatment [1] | |
| Tx | Treatment [2] | |
| D/C | Discontinue [2] | ISMP: D/C can mean discharge or discontinue and is misread; write the word [4]. |
| OD | Right eye — Latin oculus dexter [1][2] | ISMP: OD, OS, OU are mistaken as AD, AS, AU; write right eye, left eye or each eye [4]. |
| OS | Left eye — Latin oculus sinister [1][2] | |
| OU | Both eyes [2] | |
| AD | Right ear [2] | ISMP: AD, AS, AU are mistaken as OD, OS, OU; write right ear, left ear or each ear [4]. AD also stands for Aleutian disease [1]. |
| AS | Left ear [2] | |
| AU | Both ears [2] |
Frequently asked questions
What does SID mean on a veterinary prescription?
What is the difference between EOD and q.d.?
Why should OD and AD be avoided?
ISMP reports that OD, OS and OU are mistaken for AD, AS and AU and vice versa, and recommends writing right eye, left eye, each eye, right ear, left ear or each ear [4].
Related tools and references
More veterinary abbreviations
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