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Improving Patient Safety In Rural Hospitals

Commonly Misinterpreted Abbreviations

Abbreviation Intended Meaning Common Error
U Units Mistaken as zero or a four resulting in overdose. Also mistaken for "cc" (cubic centimeters) when poorly written.
mg Micrograms Mistaken for "mg" (milligrams) resulting in a ten-fold overdose
*Q.D. Latin abbreviation for every day The period after the "Q" has sometimes been mistaken for an " I, " and the drug has been given "QID" (four times daily) rather than daily.
*Q.O.D. Latin abbreviation for every other day Misinterpreted as "QD" (daily) or "QID" (four times daily). If the "O" is poorly written, it looks like a period or "I." SC or SQ
Subcutaneous   Mistaken as "SL" (sublingual) when poorly written.
TIW Three times a week Misinterpreted as "three times a day" or "twice a week"
D/C Discharge; also discontinue. Patient's medications have been prematurely discontinued when D/C, (intended to mean "discharge") Misinterpreted as "discontinue," because it was followed by a list of drugs.
HS Half strength Misinterpreted as the Latin abbreviation "HS" (hour of sleep).
Trailing Zero ______.0 Missing decimal point
cc Cubic centimeters Mistaken as "U" (units when poorly written.)
AU,AS,AD Latin abbreviation for both ears; left ear; right ear Misinterpreted as the Latin abbreviation "OU" (both eyes); "OS" (left eye); "OD" (right eye)

*High Percentage of Errors

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Copyright © 1998-99 National Coordinating Council for Medication Error Reporting and Prevention. All Rights Reserved. Permission is hereby granted to reproduce information contained herein provided that such reproduction shall not modify the text and shall include this copyright notice.

Current as of October 2001

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