| Abbreviation | Latin | Meaning |
|---|---|---|
| aa | ana | of each |
| ad | ad | up to |
| a.c. | ante cibum | before meals |
| a.d. | auris dextra | right ear |
| ad lib. | ad libitum | use as much as one desires; freely |
| admov. | admove | apply |
| agit | agita | stir/shake |
| alt. h. | alternis horis | every other hour |
| a.m. | ante meridiem | morning, before noon |
| amp | ampule | |
| amt | amount | |
| aq | aqua | water |
| a.l., a.s. | auris laeva, auris sinistra | left ear |
| A.T.C. | around the clock | |
| a.u. | auris utraque | both ears |
| bis | bis | twice |
| b.d./b.i.d. | bis in die | twice daily |
| B.M. | bowel movement | |
| bol. | bolus | as a large single dose (usually intravenously) |
| B.S. | blood sugar | |
| B.S.A | body surface areas | |
| BUCC | bucca | inside cheek |
| cap., caps. | capsula | capsule |
| c, c. | cum | with (usually written with a bar on top of the "c") |
| cib. | cibus | food |
| cc | cum cibo | with food, (but also cubic centimetre) |
| cf | with food | |
| comp. | compound | |
| cr., crm | cream | |
| CST | Continue same treatment | |
| D5W | dextrose 5% solution (sometimes written as D5W) | |
| D5NS | dextrose 5% in normal saline (0.9%) | |
| D.A.W. | dispense as written (i.e., no generic substitution) | |
| dc, D/C, disc | discontinue | |
| dieb. alt. | diebus alternis | every other day |
| dil. | dilute | |
| disp. | dispersible or dispense | |
| div. | divide | |
| d.t.d. | dentur tales doses | give of such doses |
| D.W. | distilled water | |
| elix. | elixir | |
| e.m.p. | ex modo prescripto | as directed |
| emuls. | emulsum | emulsion |
| et | et | and |
| eod | every other day | |
| ex aq | ex aqua | in water |
| fl., fld. | fluid | |
| ft. | fiat | make; let it be made |
| g | gram | |
| gr | grain | |
| gtt(s) | gutta(e) | drop(s) |
| H | hypodermic | |
| h, hr | hora | hour |
| h.s. | hora somni | at bedtime |
| ID | intradermal | |
| IM | intramuscular (with respect to injections) | |
| inj. | injectio | injection |
| IP | intraperitoneal | |
| IV | intravenous | |
| IVP | intravenous push | |
| IVPB | intravenous piggyback | |
| L.A.S. | label as such | |
| LCD | coal tar solution | |
| lin | linimentum | liniment |
| liq | liquor | solution |
| lot. | lotion | |
| mane | mane | in the morning |
| M. | misce | mix |
| m, min | minimum | a minimum |
| mcg | microgram | |
| m.d.u. | more dicto utendus | to be used as directed |
| mEq | milliequivalent | |
| mg | milligram | |
| mist. | mistura | mix |
| mitte | mitte | send |
| mL | millilitre | |
| nebul | nebula | a spray |
| N.M.T. | not more than | |
| noct. | nocte | at night |
| non rep. | non repetatur | no repeats |
| NS | normal saline (0.9%) | |
| 1/2NS | half normal saline (0.45%) | |
| N.T.E. | not to exceed | |
| o_2 | both eyes, sometimes written as o2 | |
| o.d. | oculus dexter | right eye |
| o.p.d. | once per day | |
| o.s. | oculus sinister | left eye |
| o.u. | oculus uterque | both eyes |
| oz | ounce | |
| per | per | by or through |
| p.c. | post cibum | after meals |
| pig./pigm. | pigmentum | paint |
| p.m. | post meridiem | evening or afternoon |
| PRN, prn | pro re nata | as needed |
| p.o. | per os | by mouth or orally |
| p.r. | by rectum | |
| pulv. | pulvis | powder |
| PV | per vaginam | via the vagina |
| q | quaque | every |
| q.a.d. | quoque alternis die | every other day |
| q.a.m. | quaque die ante meridiem | every day before noon |
| q.d.s. | quater die sumendus | four times a day |
| q.p.m. | quaque die post meridiem | every day after noon |
| q.h. | quaque hora | every hour |
| q.h.s. | quaque hora somni | every night at bedtime |
| q.1h, q.1° | quaque 1 hora | every 1 hour; (can replace "1" with other numbers) |
| q.d. | quaque die | every day |
| q.i.d. | quater in die | four times a day |
| q.o.d. | every other day | |
| qqh | quater quaque hora | every four hours |
| q.s. | quantum sufficiat | a sufficient quantity |
| QWK | every week | |
| R | rectal | |
| rep., rept. | repetatur | repeats |
| RL, R/L | Ringer's lactate | |
| s | sine | without (usually written with a bar on top of the "s") |
| s.a. | secundum artum | use your judgement |
| SC, subc, subcut, subq, SQ | subcutaneous | |
| sig | write on label | |
| SL | sublingually, under the tongue | |
| sol | solutio | solution |
| s.o.s., si op. sit | si opus sit | if there is a need |
| ss | semis | one half |
| stat | statim | immediately |
| supp | suppositorium | suppository |
| susp | suspension | |
| syr | syrupus | syrup |
| tab | tabella | tablet |
| tal., t | talus | such |
| tbsp | tablespoon | |
| troche | trochiscus | lozenge |
| tsp | teaspoon | |
| t.i.d. | ter in die | three times a day |
| t.d.s. | ter die sumendum | three times a day |
| t.i.w. | three times a week | |
| top. | topical | |
| T.P.N. | total parenteral nutrition | |
| tr, tinc., tinct. | tincture | |
| u.d., ut. dict. | ut dictum | as directed |
| ung. | unguentum | ointment |
| U.S.P. | United States Pharmacopoeia | |
| vag | vaginally | |
| w | with | |
| wf | with food (with meals) | |
| w/o | without | |
| X | times | |
| Y.O. | years old |
To avoid ambiguity, the following abbreviations are not recommended [1] [2]:
- a.u., a.s., a.d. - Latin for both, left and right ears; the "a" can be misread to be an "o" and interpreted to mean both, right or left eyes
- bt - intended to mean "bedtime", but can be misread as "bid" or twice daily.
- d/c - can mean "discontinue" or "discharge"
- h.s. - can mean half strength or "hour of sleep"
- IJ - intended to mean "injection", but can be misread as "IV"
- IN - intended to mean "intranasal", but can be misread as "IM" or "IV"
- IU - intended to mean "international unit", but can be misread as "IV" or "10"
- o.d., o.s., o.u. - the "o" can be misread as "a".
- o.d. - can mean "once daily" or "right eye".
- OJ - intended to mean "orange juice" but can be misread as "OD" or "OS"
- q4PM - intended to mean "at 4 PM", but can be misread as every 4 hours
- q.d., q1d - intended to mean "every day" but can be misread as "q.i.d." or 4 times a day
- q.o.d. - meant "every other day" but the "o" can be interpreted as "." or "i" resulting in double or eight times the frequency
- SC - meant "subcutaneous" but mistaken for "SL" for "sublingual"
- SQ - meant "subcutaneous" but mistaken for "5Q" or 5 every dose
- 'ss - intended to mean "sliding scale" or "1/2", but can be mistaken as "55"
- 'SSI, SSRI - intended to mean "sliding scale insulin" or "sliding scale regular insulin", but can be mistaken as "strong solution of iodine" or "selective serotonin reuptake inhibitor
- T.I.W - meant 3 times a week but mistaken for twice a week
- U - meant "units" but mistaken for "0", "4" (so "4U" can become "40" and the "U" is assumed), or misread as "cc" when poorly written; conversely cc can be mistaken for "U"
- μg - meant "microgram" but mistaken for "mg"; this 1000-fold error can cause potentially fatal misunderstandings
