alt.h. = Every other hour. From the Latin phrase “alternis horis” meaning “every other
hour.”

a.t.c. = Around the clock. This does not refer to continuous use of medication but rather
the use of medication and specified intervals throughout the day to maximize symptom
control. This abbreviation is sometimes written for pain medications.

b.i.d. = Twice a day. From he Latin phrase «bis in die,» meaning «twice a day.»

b.t. = Bedtime.

c or c with a line above it = With. From the Latin word “cum” meaning “with.”
This is used to state what to take the medication with.

cc = With food. From the Latin phrase “cum cibo” meaning “with
food.” This means to take the medication with food.

d.a.w. = Dispense as written. This means that the pharmacist
should fill the prescription as written and not substitute a generic
medication.

dieb alt. = Every other day. From the Latin phrase “diebus alternis” meaning “every other day.”

div. = divide. Some pills can be split, usually by a demarcated line in the middle of the pills. This is a way to half some doses.

e.m.p. = As directed. From the Latin phrase “ex modo prescripto” meaning “as directed.”

n.m.t. = Not more than.

noct. = At night. From the Latin word “nocte” meaning “night.”

n.t.e. = Not to exceed.

p.c. = After meals. From the Latin phrase “post cibum” meaning “after meals.”

p.o. = By mouth. From the Latin phrase “per os” meaning “by mouth.”

p.r. = By rectum. From the Latin phrase “per rectum” meaning “by rectum.”

p.r.n. = As needed. This is one of the most common abbreviations and stands for “pro re nata,” Latin for “as the circumstances arises.”

q.(followed by a number and sometimes the letter h.) = Every x number of hours. For example q.8h means to use the medication every 8 hours. Another common abbreviation is q.4h. In these abbreviations, the letter “q” stands for “quaque” which means “every.”

q.a.d. = See q.o.d.

q.a.m. = Every morning. From the Latin phrase “quaque ante meridiem,” meaning “every before noon.”

q.d. = Once a day. From the Latin phrase «quaque die,» meaning «every day.» This abbreviation is also written as quotid (because the Latin word «quotidianus» means «daily.» Many hospitals advise avoiding use of this abbreviation because it is often confused with q.i.d. (four times a day) or q.o.d. (every other day) which can have serious consequences for the patient.

q.d.s. = Four times a day. From the Latin phrase “qauter die sumendus” meaning “ four times a day.”

q.h. = Every hour. From the Latin phrase «quaque hora,» meaning «every hour.»

q.h.s. = At bedtime. From the Latin phrase «quaque hora somni,» meaning «every hour of sleep.»

q.i.d. = Four times a day. From the Latin phrase «quarter in die,» meaning «four times a day.»

q.l. = As much as one wants. From the Latin phrase «quantum libet,» meaning «as much as one pleases.»

q.o.d. = Every other day. From the Latin phrase «quaque altera die,» meaning «every other day.»
Technically, the abbreviation should really be q.a.d. (and some people use it this way), but sometimes weird things happen with medical abbreviations.

q.p.m. = Every day after noon. From the Latin phrase “quaque post meridiem” meaning “every after noon.”

q.q.h. = Every four hours. From the Latin phrase “quarter quaque hora” meaning “every four hours.”

q.s. = As much as is needed. From “quantum sufficiat,” “quantum sufficit,” and “quantum satis,” Latin phrases which all mean «as much as suffices» or «quantity required.»

qwk = Every week. The «q» is from the Latin word “quaque” meaning “every” followed by the word week.

s with a line above it = Without. From the Latin word “sine” meaning “without.”
s.a. = Use your judgment. From the Latin phrase “secundum artem” meaning according to the art.

sl = Sublingual (under the tongue).

stat. = Immediately. From the Latin word “statim” meaning “immediately.”

tbsp. = Tablespoon.

t.i.d. = Three times a day. From the Latin phrase «ter in die,» meaning «three times a day.»

t.i.w. = Three times a week. From the Latin words “ter in” meaning three times, followed by the word “week.”

top. = Topical (applied on the skin).

tsp = Teaspoon.

w/a = While awake.

wf = With food.

X = The number of times one should do something. For example x3 could mean to use 3 pills.