Science, Art, Litt, Science based Art & Science Communication

Qs people asked me on science and my replies to them - part 134

Medical symbols and abbreviations

Q: What does a black triangle on a medicine strip indicate?

Krishna:

This black triangle symbol is very important in drug monitoring after it is released into the public domain. It indicates that the medication is new to the market, or that an existing medicine (or vaccine) is being used for a new reason or by a new route of administration.

The black triangle also highlights the need for surveillance of any Adverse drug reactions (ADRs) that might arise from the use of a new medication. Patients who are using these medicines or their relatives are encouraged to voluntarily report ADRs (however minor) to gather more information and gain more understanding of a new medication.

After a new medicine (or vaccine) has been brought to the market there is still a lot that can be learned about the drug from its widespread use. This is really important as clinical researchers might not have the conditions to test the drug in all possible scenarios and even if they tested and found some negative reactions, the drug companies might not be honest about the disclosures. Similarly, if an existing drug is being used in a situation where it was not used before or if it is being given by a different route of administration much can still be learned about its new or modified use.

The black triangle label generally stays with the new drug (or new use of an existing drug) for at least 5 years, when it is reviewed, and after this time the black triangle label may or may not be discontinued.

Q: What does Rx on medical prescription mean?

Krishna:

The Roman letter R, which stands for recipe, the imperative form of the verb "to receive" (from which comes the word recipient). In other words, the symbol is a command, meaning in effect "take this". The symbol itself dates from medieval times, and has come down to us to signify "prescription" and sometimes even "medicine" in a generic sense. "Rx" means "prescription". And based on this it is also common to use Bx for biopsy, Cx for cervix, Hx for history, Ex for examination, and so on.

Q: Doctors write strange things on prescription slips. Most of the time, we don't understand what they are . How can we find out how to use the medicines?

Krishna: Why don't you ask your doctor if you don't understand something on prescription papers? You should never feel shy to ask a doctor.

Some Latin abbreviations commonly used in daily prescriptions :

OD - one time a day

BD- twice a day

TDS- three times a day

QID- four times a day

HS- at bedtime

SOS - As and when required

AC- before meals

PC - after meals.

I am giving below a chart of some of the medical abbreviations doctors use along with full meaning.

Abbreviation	Meaning / Intended Meaning	Notes About Confusion	Category
1/2NS	one-half normal saline (0.45%)		drug or class name
5-ASA	5-aminosalicylic acid	Better to spell out drug name; can be misinterpreted as five tablets of aspirin per FDA	drug or class name
a	before		time
A.M.	morning		time
aa	of each		measurement
AAA	abdominal aortic aneurysm (called a "triple-A")	Can be misinterpreted as 'apply to affected area'	medical condition
AAA	apply to affected area	Can be misinterpreted as 'abdominal aortic aneurysm'	route of administration
ac	before meals		time
achs	before meals and at bedtime		time
AD	right ear		route of administration
ad lib	freely; as much as desired		time
ad sat.	to saturation		other
ad.	to; up to	Caution not to confuse with AD (meaning right ear)	measurement
ALT	alanine aminotransferase		lab
alt.	alternate		time
alt. h.	every other hour		time
am, A.M.	in the morning; before noon		time
amp	ampule		dosage form
amt.	amount		measurement
ant.	anterior		other
ante	before		time
ap	before dinner		time
APAP	acetaminophen	Better to spell out drug name "acetaminophen"	drug or class name
aPTT	activated partial thromboplastin		lab
AQ, aq	water		other
a.s., AS	left ear		route of administration
ASA	aspirin	Better to spell out drug name "aspirin"	drug or class name
AST	aspartate aminotransferase		lab
ATC	around the clock		time
AU	each ear; both ears		route of administration
AZT	zidovudine	Better to spell drug name out; can be misinterpreted as azathioprine per FDA	drug or class name
Ba	barium		drug or class name
BCP	birth control pills		drug or class name
Bi	bismuth		drug or class name
bid, BID	twice a day		time
BM	bowel movement		other
BMI	body mass index		vitals
bol	bolus		measurement
BP	blood pressure		vitals
BPH	benign prostatic hypertrophy		medical condition
BS	blood sugar		lab
BSA	body surface area		vitals
BT	bedtime	In U.S., 'hs' or 'HS' is more commonly used for bedtime	time
c	with		other
C.C.	chief complaint		other
c/o	complaints of		other
C&S	culture and sensitivity		lab
CABG	coronary artery bypass graft		other
CaCO₃	calcium carbonate		drug or class name
CAD	coronary artery disease		medical condition
CAP	cancer of the prostate	Do not confuse with "capsule"	medical condition
cap.	capsule	Do not confuse with "cancer of the prostate"	dosage form
CBC	complete blood count		lab
cc	cubic centimeter	Can also mean "with food"	measurement
CD	controlled delivery		drug release technology
CF	cystic fibrosis		medical condition
cm	centimeter		measurement
CNS	central nervous system		other
conc	concentrated		other
CPZ	Compazine	Better to spell drug name out; can be misinterpreted as chlorpromazine per FDA	drug or class name
CR	controlled-release		drug release technology
cr, crm	cream		dosage form
CV	cardiovascular		other
CXR	chest x-ray		lab
D/C, dc, disc.	discontinue OR discharge	Multiple possible meanings; spell out instead of using "D/C"	other
D5/0.9 NaCl	5% dextrose and normal saline solution (0.9% NaCl)		drug or class name
D5 1/2/NS	5% dextrose and half normal saline solution (0.45% NaCl)		drug or class name
D5NS	dextrose 5% in normal saline (0.9%)		drug or class name
D5W	5% dextrose in water		drug or class name
DAW	dispense as written		other
DBP	diastolic blood pressure		lab
dil.	diluted		other
disp	dispense		other
div	divide		other
DKA	diabetic ketoacidosis		medical condition
dL	deciliter		measurement
DM	diabetes mellitus		medical condition
DO	Doctor of Osteopathic Medicine		medical specialty
DOB	date of birth		other
DPT	diphtheria-pertussis-tetanus	Better to spell out vaccine name; can be misinterpreted as Demerol-Phenergan-Thorazine per FDA	drug or class name
DR	delayed-release		drug release technology
DVT	deep vein thrombosis		medical condition
DW	dextrose in water, diabetes mellitus or distilled water	Multiple possible meanings; spell out instead of using "DW"	other
EC	enteric-coated		drug release technology
EENT	Eye, Ear, Nose, and Throat		Medical Specialty
elix.	elixir		dosage form
emuls.	emulsion		dosage form
ER	extended-release	Can also mean "emergency room"	drug release technology
ER	emergency room	Can also mean "extended-release"	other
ETOH	ethyl alcohol		drug or class name
F	Fahrenheit		lab
f or F	female		other
FBS	fasting blood sugar		lab
FDA	Food and Drug Administration		other
Fe	Iron		drug or class name or lab
FFP	fresh frozen plasma		drug or class name
fl or fld	fluid		measurement
ft	foot		measurement
G, or g, or gm	gram	"g" is preferred symbol	measurement
garg	gargle		route of administration
GERD	gastroesophageal reflux disease		medical condition
GI	gastrointestinal		other
gr.	grain	Apothecary measurement (obsolete and may be misinterpreted as gram; do not use)	measurement
GTT	glucose tolerance test	Can be confused with gtt for drops	lab
gtt, gtts	drop, drops	Can be confused with GTT for glucose tolerance test	measurement
GU	genitourinary		other
guttat.	drop by drop		measurement
h, or hr.	hour		time
h/o	history of		other
H&H	hematocrit and hemoglobin		lab
H₂	histamine 2		other
H₂0	water		other
HAART	highly active antiretroviral therapy		drug or class name
HCT, or Hct	hematocrit		lab
HCT	hydrocortisone	Better to spell out drug name; can be misinterpreted as hydrochlorothiazide per FDA	drug or class name
HCTZ	hydrochlorothiazide	Better to spell out drug name; can be misinterpreted as hydrocortisone per FDA	drug or class name
HR	heart rate		vitals
HS	half-strength	better to spell out; do not mistake for "bedtime"	measurement
hs or HS	at bedtime, hours of sleep	Do not misinterpret as 'half-strength'	time
HTN	hypertension		medical condition
hx	history		other
IBW	ideal body weight		lab
ID	intradermal OR infectious disease	Multiple possible meanings; spell out word instead of using "ID"	route of administration; other
IJ	injection	better to spell out 'injection'	route of administration
IM	intramuscular		route of administration
IN	intranasal		route of administration
inf	infusion		route of administration
inj.	injection		route of administration
instill.	instillation		route of administration
IP	intraperitoneal		route of administration
IR	immediate-release		drug release technology
IU	international unit	Mistaken as IV (intravenous) or 10 (ten); Instead spell out "units" per Joint Commission's "Do Not Use" List of Abbreviations
IUD	intrauterine device		dosage form
IV	intravenous		route of administration
IVP	intravenous push	Could be confused with 'intravenous pyelogram'	route of administration
IVPB	intravenous piggyback		route of administration
J	joule		lab
K	potassium		drug or class name
KOH	potassium hydroxide		drug or class name
L	liter		measurement
LA	long-acting		drug release technology
lab	laboratory		other
lb.	pound		measurement
LDL	low-density lipoprotein		lab
LFT	liver function tests		lab
Li	lithium		drug or class name
liq.	liquid		dosage form
LMP	last menstrual period		other
lot	lotion		dosage form
LPN	licensed practical nurse		medical specialty
LR	lactated ringer (solution)		drug or class name
mane	in the morning		time
mcg	microgram	Can be misinterpreted to mean "mg" or milligram, better to spell out 'microgram'	measurement
MD	medical doctor		medical specialty
MDI	metered-dose inhaler		dosage form
mEq	milliequivalent		measurement
mEq/L	milliequivalent per liter		measurement
Mg	magnesium		drug or class name
mg	milligram		measurement
MgSO₄	magnesium sulfate	May be confused with "MSO4" (morphine sulfate), spell out "magnesium sulfate" - Joint Commission's "Do Not Use" List of Abbreviations	drug or class name
mL	milliliter		measurement
mm	millimeter		measurement
mm of Hg	millimeters of mercury		measurement
mMol	millimole		measurement
MMR	measle-mumps-rubella (vaccine)		drug or class name
mol wt	molecular weight		measurement
MR	modified-release		drug release technology
MS	morphine sulfate or magnesium sulfate	Can mean either morphine sulfate or magnesium sulfate, spell out drug name - Joint Commission's "Do Not Use" List of Abbreviations	drug or class name
MSO4	morphine sulfate	May be confused with "MgSO4"; instead spell out "morphine sulfate" - Joint Commission's "Do Not Use" List of Abbreviations	drug or class name
n or noct.	in the night		time
N/A	not applicable		other
N/V, N&V	nausea and vomiting		other
Na	sodium		lab or drug or class name
NAS	intranasal		route of administration
NDC	National Drug Code		other
NGT	nasogastric tube		route of administration
NH₃	ammonia		other
NKA	no known allergies		other
NKDA	no known drug allergies		other
noct. maneq.	night and morning		time
NP	nurse practitioner		medical specialty
NPO, n.p.o.	nothing by mouth	Preferred by AMA to spell out "nothing by mouth"	route of administration
NS	normal saline		drug or class name
NSAID	nonsteroidal anti-inflammatory drug		drug or class name
NTE	not to exceed		other
O₂	oxygen		other
OC	oral contraceptive		drug or class name
o.d., OD	right eye	Can also mean "overdose" or "once daily"; better to spell out	route of administration, ophthalmic abbreviations
o.d.	once per day	Preferred in the UK; Can also mean "overdose" or "right eye"; better to spell out	time
OJ	orange juice		other
OM	otitis media		medical condition
o.s., OS	left eye		route of administration, ophthalmic abbreviations
OTC	over-the-counter		other
o.u., OU	both eyes		route of administration, ophthalmic abbreviations
oz	ounce		measurement
p	after		time
p.r.n., prn	as needed		time
PA	physician assistant		medical specialty
pc	after meals		time
PCA	patient-controlled analgesia		other
PE	physical exam, pulmonary embolism		other
per	by or through		route of administration
per neb	by nebulizer		route of administration
per os	by mouth, orally	AMA prefers to spell out "by mouth" or "orally"; can be mistaken as "os" meaning left eye per FDA	route of administration
PFT	pulmonary function tests		lab
pH	hydrogen ion concentration		other
PharmD	Doctor of Pharmacy		medical specialty
PM	evening		time
PMH	past medical history		other
PO, p.o.	orally or by mouth	AMA prefers to spell out "by mouth" or "orally"	route of administration
PR, p.r.	per the rectum		route of administration
PT	prothrombin time		lab
PTT	partial thromboplastin time		lab
pulv	powder		dosage form
PV	per the vagina		route of administration
q	every		time
q.s., qs	as much as needed; a sufficient quantity		measurement
q12h	every 12 hours		time
qd, q1d	daily		time
q2h	every 2 hours		time
q3h	every 3 hours		time
q4h	every 4 hours		time
q6h	every 6 hours		time
q6PM, etc	every evening at 6 PM		time
q8h	every 8 hours		time
qam	every morning		time
qd, QD	every day	Mistaken as q.i.d; Instead write "daily" or "every day" per Joint Commission's "Do Not Use" List of Abbreviations	time
qh	every hour		time
qhs	each night at bedtime	Can be confused with "qh" meaning every hour; better to spell out	time
qid	four times a day		time
qn	Nightly or at bedtime	Not commonly used in U.S.; 'hs' more common for bedtime	time
qod, QOD, q.o.d	every other day	Can be mistaken as qd (daily) or qid (four times daily); Instead spell out "every other day" per Joint Commission's "Do Not Use" List of Abbreviations	time
q.s. ad	add sufficient quantity to make		measurement
RA	rheumatoid arthritis		medical condition
RDA	recommended daily allowances		other
RE	right eye		route of administration, ophthalmic abbreviations
rep	repeats		time
RN	registered nurse		medical specialty
RPh	pharmacist		medical specialty
Rx	prescription		other
s	without		other
s.o.s.	if necessary		other
sa	according to the art; best practice		other
SA	sustained action		drug release technology
SBP	systolic blood pressure		vital sign
SID	Used ONLY in Veterinary medicine to mean "once daily"	Can be confused to mean BID (twice daily) and QID (four times daily); pharmacists should clarify abbreviations with DVM, if needed.	time; used in Veterinary medicine ONLY
sig codes	medical or prescription abbreviations		other
Sig.	write on label		other
SL, s.l.	sublingual, under the tongue		route of administration
SNRI	serotonin/norepinephrine reuptake inhibitor		drug or class name
SOB	shortness of breath		other
sol	solution; in solution		dosage form
sp gr	specific gravity		lab
SQ, SC, sub q	subcutaneously	Use caution as "SC" can be mistaken for "SL," meaning sublingual per FDA	route of administration
SR	sustained release		drug release technology
ss	sliding scale (insulin) OR 1/2 (apothecary; obsolete)	Use caution; can be misinterpreted; better to spell out "sliding scale" or "one-half"	other
SSI	Sliding scale insulin		other
SSRI	sliding scale regular insulin OR selective serotonin reuptake inhibitor	Spell out words to avoid confusion	other
stat	immediately		time
STD	sexually transmitted diseases		medical condition
sup.	superior		other
supf.	superficial		other
supp	suppository		dosage form
susp	suspension		dosage form
syr.	syrup		dosage form
T	temperature		vital sign
tab	tablet		dosage form
tbsp	tablespoon		measurement
TIA	transient ischemic attack		medical condition
TID, t.i.d.	three times a day		time
tid ac	three times a day before meals		time
TIN, t.i.n.	three times a night		time
tinct., tr	tincture		dosage form
TIW, tiw	3 times a week	Spell out; can be confused with TID (three times a day)	time
top.	topical		route of administration
TO	telephone order
TPN	total parenteral nutrition		drug or class name
TR	timed-release		drug release technology
troche	lozenge		dosage form
TSH	thyroid stimulating hormone		lab
tsp	teaspoon		measurement
Tx	treatment		other
U or u	unit	Mistaken as the number "0" (zero), the number "4" (four), or "cc". Prescriber should instead spell out "unit" per Joint Commission's "Do Not Use" List of Abbreviations	measurement
UA	urinalysis		lab
ud, ut dict, UD	as directed		other
ung	ointment		dosage form
UTI	urinary tract infection		medical condition
vag, pv	via the vagina		route of administration
VLDL	very low density lipoprotein		lab
vol %	volume percent		measurement
vol.	volume		measurement
w/o	without		other
w/v	weight in volume		measurement
WBC	white blood cell		lab
WNL	within normal limits		lab
wt.	weight		vital sign
x	multiplied by		other
XL	extended-release		drug release technology
XR	extended-release		drug release technology
XT	extended-release		drug release technology
yo	years old		other
yr	year		time
Zn	zinc		drug or class drug or class name
μEq	microequivalent		measurement
μg, mcg	microgram	μg or mcg can be misinterpreted as "mg", better to spell out 'microgram'	measurement
μL	microliter		measurement

Table source: drugs.com

There is symbol to recognize genuine doctors in India:

This is a signage to indicate that the doctors who use it have studied “modern medicine”. Inadequate clinical evidence supporting alternative medicine made the country adopt an affirmative symbol for modern medicine.