The 2004 National Patient Safety Goals of The Joint Commission (TJC) requires the elimination of dangerous abbreviations in an effort to promote patient safety by reducing medication errors. To achieve this goal, TJC developed a list of abbreviations, acronyms, and symbols that health care organizations must include in their “do not use” list. An abbreviation on the “do not use” list should not be used in any of its forms—uppercase or lowercase, with or without periods. For example, if Q.D. is on the organization’s list, health care organizations cannot use QD or qd because any of those variations are confusing and can be misinterpreted.
| Abbreviation | Potential Problem | Preferred Term |
| U (for unit) | Mistaken as zero, four, or cc | Write “unit” |
| IU (for international unit) | Mistaken as IV (intravenous) or 10 (ten) | Write “international unit” |
| Q.D., QD, q.d., qd (daily) | Mistaken for each other | Write “daily” |
| Q.O.D., QOD, q.o.d., qod (every other day) | Period after “Q” mistaken for “I” and the “O” mistaken for “I” | Write “every other day” |
| Trailing zero (e.g., 5.0 mg); lack of leading zero (e.g., .5 mg) | Decimal point is missed | Always write a zero before a decimal point (0.5 mg) and never write a zero by itself after a decimal point (5 mg) |
| MS, MSO4, MgSO4 | Confused for one another; can mean morphine sulfate or magnesium sulfate | Write “morphine sulfate” or “magnesium sulfate” |
In addition, TJC requires an organization to identify and apply at least another three “do not use” abbreviations, acronyms, or symbols of its own choosing. The following list was developed by TJC for organizations to consider including on their list.
| μg (for micrograms) | Mistaken for mg (milligrams) resulting in one thousand-fold-dosing overdose | Write “mcg” |
| H.S. (for half-strength or Latin abbreviation for bedtime) | Mistaken for either half-strength or hour of sleep (at bedtime); q.H.S. mistaken for every hour; all can result in dosing error | Write “half-strength” or “at bedtime” |
| T.I.W. (for three times per week) | Mistaken for three times per day or twice weekly, resulting in an overdose | Write “3 times weekly” or “three times weekly” |
| S.C. or S.Q. (for subcutaneous) | Mistaken as SL for sublingual, or “5 every” | Write “Sub-Q, ” “subQ, ” or “subcutaneously” |
| D/C (for discharge) | Interpreted as discontinue whatever medications follow (typically discharge meds) | Write “discharge” |
| c.c. (for cubic centimeter) | Mistaken for U (units) when poorly written | Write “ml” for milliliters |
| A.S., A.D., A.U. (Latin abbreviation for left, right, or both ears) | Mistaken for OS, OD, OU, etc. | Write “left ear, ” “right ear, ” or “both ears” |
| > (greater than) < (less than) | Misinterpreted as number 7 or letter “L” | Write “greater than” or “less than” |
| Abbreviations for drug names | Misinterpreted due to similar abbreviations for multiple drugs | Write drug names in full |