Prohibited Abbreviations |
Abbreviations |
Intended Meaning |
Misinterpretation |
Suggested |
1/d |
one daily |
tid |
1 daily |
AD, AS, AU |
right ear, left ear, each ear |
OD, OS, OU |
right ear, left ear, each ear |
BT |
bedtime |
bid (twice daily) |
bedtime |
cc |
cubic centimeters |
"u" (units) |
mL |
D/C |
discharge or discontinue |
Premature discontinuation of medications if D/C (intended
to mean "discharge") has been misinterpreted as
"discontinued" when followed by a list of discharge
medications. |
Discharge or Discontinue |
hs (h.s.) |
at bedtime, hours of sleep |
half-strength |
at bedtime |
HS |
half-strength |
bedtime |
half-strength |
IJ |
injection |
IV or intrajugular |
injection |
IN |
intranasal |
IM or IV |
intranasal or NAS |
IU |
international unit |
IV (intravenous) or 10 (ten) |
units |
od (o.d.) |
once daily |
"right eye" (OD-oculus dexter), leading to oral
liquid medications administered in the eye. |
daily |
OD, OS, OU |
right eye, left eye, each eye |
AD, AS, AU (right ear, left ear, each ear) |
right eye, left eye, each eye |
OJ |
orange juice |
OD or OS (right or left eye); drugs meant to be diluted
in orange juice may be given in the eye. |
orange juice |
per os |
by mouth or orally |
"os" can be mistaken as "left eye"
(OS-oculus sinister) |
PO, by mouth, orally |
q.d. or qd |
every day |
q.i.d., especially if the period after the "q"
or the tail of the "q" is misunderstood as an "l." |
daily |
q.o.d. or QOD |
every other day |
"q.d." (daily) or "q.i.d." (4 times
daily) if the "o" is poorly written |
every other day |
q1d |
daily |
q.i.d. (r times daily) |
daily |
q6PM, etc. |
early evening at 6 p.m. |
every 6 hours |
"6 PM nightly," or "6 PM daily." |
qhs (q.h.s.) |
at bedtime |
"qhr" or "every hour" |
at bedtime |
qn |
nightly |
qh (every hour) |
nightly |
SC, SQ, sub q |
subcutaneous |
SC mistaken as SL (sublingual); SQ mistaken as "5
every;" the "q" in "sub q" has been
mistaken as "every" (e.g., a heparin dose order
sub q 2 hours before surgery misunderstood as every 2 hours
before surgery. |
"subcut" or "subcutaneously" |
ss |
sliding scale (insulin) or � (apothecary) |
55 |
Spell out "sliding scale"; use "one-half"
or "�." |
SSI |
sliding scale insulin |
Strong solution of iodine (Lugol's) |
sliding scale (insulin) |
SSRI |
sliding scale regular insulin |
selective-serotonin reuptake inhibitor |
sliding scale (insulin) |
TIW, tiw, t.i.w. |
3 times a week |
"3 times a day" or "twice in a week." |
3 times weekly |
U or u |
unit |
Number 0 or 4, causing a 10-fold overdose or greater (e.g.,
4U seen as "40" or "4u" seen as "44");
mistaken as "cc" so dose given in volume instead
of unites (e.g., 4u seen as 4 cc). |
unit |
Symbols |
Symbols |
Intended Meaning |
Misinterpretation |
Suggested |
/ (slash mark) |
separates 2 doses or indicates "per" |
number 1 ("25 units/10 units" read as "110
units.") |
Do not use a slash mark to separate doses.� Spell out
the word "per." |
+ |
"plus" or "and" |
4 |
and |
>� or� < |
"greater than" or "less than" |
opposite of intended |
"greater than" or "less than" |
& |
and |
2 |
and |
@ |
at |
2 |
at |
Apothecary symbol |
Minim |
mL |
Use the metric system |
x3d |
for 3 days |
3 doses |
for 3 days |
Apothecary symbol |
dram |
3 |
Use the metric system |
° |
hour |
zero (e.g., q2� seen as q 20) |
hr, h, or hour |
Fg |
microgram |
mg |
mcg |
Dose Designations and
Other Information |
Dose Designation / Information |
Intended Meaning |
Misinterpretation |
Suggested |
"0" (zero) after decimal point (1.0) |
1 mg |
10 mg if the decimal point is not seen. |
Do not use terminal zeros for doses expressed in whole
numbers. |
Large doses without properly placed commas (e.g., 100000
units; 1000000 units) |
100,000 units; 1,000,000 units |
100000 has been mistaken as 10,000 or 1,000,000; 1000000
has been mistaken as 100,000. |
Use commas for dosing units at or above 1,000 or use words
such as 100 "thousand" or 1 "million"
to improve readability. |
mg. or mL. with a period following the abbreviation. |
mg, mL |
The period is unnecessary and could be mistaken as the
number 1 if written poorly |
Use mg, mL, etc., WITHOUT a terminal period. |
Name letters and dose numbers run together (e.g., Inderal40
mg) |
Inderal 40 mg |
Misread as Inderal 140 mg |
Always use a space between drug name, dose, and unit of
measure. |
No zero before decimal dose (.5 mg) |
0.5 mg |
5 mg |
Always use zero before a decimal when the dose is less
than a whole unit. |
Numerical dose and unit of measure run together (e.g.,
10mg, 100mL) |
10 mg; 100 mL |
The "m" is sometimes mistaken as a zero or 2
zeros, risking a 10- to 100-fold overdose. |
Place adequate space between the dose and unit of measure. |
Drug Name Abbrevations |
Drug Name |
Intended Meaning |
Misinterpretation |
Suggested |
ARA A |
vidarabine |
cytarabine (ARA C) |
Use complete drug name |
AZT |
zidovudine (Retrovir) |
azathioprine or aztreonam |
Use complete drug name |
CPZ |
Compazine (prochlorperazine) |
chlorpromazine |
Use complete drug name |
DPT |
Demerol-Phenergan-Thorazine |
diphtheria-pertussis-tetanus (vaccine) |
Use complete drug name |
DTO |
diluted tincture or opium, or deodorized tincture of opium |
tincture of opium |
Use complete drug name |
HCI |
hydrochloric acid or hydrochloride |
potassium chloride ("h" misinterpreted as "k") |
Use complete drug name |
HCT |
hydrocortisone |
hydrochlorothiazide |
Use complete drug name |
HCTZ |
hydrochlorothiazide |
hydrocortisone (seen as HCT250 mg) |
Use complete drug name |
MgS04 |
magnesium sulfate |
morphine sulfate |
Use complete drug name |
MS, MS04 |
morphine sulfate |
magnesium sulfate |
Use complete drug name |
MTX |
methotrexate |
mitoxantrone |
Use complete drug name |
PCA |
procainamide |
patient controlled analgesia |
Use complete drug name |
PTU |
propylthiouracil |
mercaptopurine |
Use complete drug name |
T3 |
Tylenol with codeine No. 3 |
liothyronine |
Use complete drug name |
TAC |
triamcinolone |
tetracaine, Adrenalin, cocaine |
Use complete drug name |
TNK |
TNKase |
TPA |
Use complete drug name |
ZnS04 |
zinc sulfate |
morphine sulfate |
Use complete drug name |
Stemmed Drug Names |
Stemmed Drug Names |
Intended Meaning |
Misinterpretation |
Suggested |
IV Vanc |
intravenous vancomycin |
Invanz |
Use complete drug name. |
Nitro drip |
nitroglycerin infusion |
sodium nitroprusside infusion |
Use complete drug name. |
Norflox |
norfloxacin |
Norflex |
Use complete drug name. |