MSD Manual

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The following abbreviations are used throughout the text; other abbreviations are expanded at first mention in the chapter or subchapter.

ABG arterial blood gas
ACE angiotensin-converting enzyme
ACTH adrenocorticotropic hormone
ADH antidiuretic hormone
AIDS acquired immunodeficiency syndrome
ALT alanine aminotransferase (formerly SGPT)
AST aspartate aminotransferase (formerly SGOT)
ATP adenosine triphosphate
BCG bacille Calmette-Guérin
bid 2 times a day
BMR basal metabolic rate
BP blood pressure
BSA body surface area
BUN blood urea nitrogen
C Celsius; centigrade; complement
Ca calcium
cAMP cyclic adenosine monophosphate
CBC complete blood count
cGy centigray
Ci curie
CK creatine kinase
Cl chloride; chlorine
cm centimeter
CNS central nervous system
CO2 carbon dioxide
COPD chronic obstructive pulmonary disease
CK creatine kinase
CK-MB creatine kinase muscle band isoenzyme
CPR cardiopulmonary resuscitation
CSF cerebrospinal fluid
CT computed tomography
cu cubic
D & C dilation and curettage
dL deciliter (= 100 mL)
DNA deoxyribonucleic acid
DTP diphtheria-tetanus-pertussis (toxoids/vaccine)
D/W or D dextrose in water
ECF extracellular fluid
ECG electrocardiogram
EEG electroencephalogram
ENT ear, nose, and throat
ERCP endoscopic retrograde cholangiopancreatography
ESR erythrocyte sedimentation rate
F Fahrenheit
FDA U.S. Food and Drug Administration
ft foot; feet (measure)
FUO fever of unknown origin
g gram
GFR glomerular filtration rate
GI gastrointestinal
G6PD glucose-6-phosphate dehydrogenase
GU genitourinary
Gy gray
h hour
Hb hemoglobin
HCl hydrochloric acid; hydrochloride
HCO3 bicarbonate
Hct hematocrit
Hg mercury
HIV human immunodeficiency virus
HLA human leukocyte antigen
HMG-CoA hydroxymethyl glutaryl coenzyme A
Hz hertz (cycles/second)
ICF intracellular fluid
ICU intensive care unit
IgA, etc immunoglobin A, etc
IL interleukin
IM intramuscular(ly)
INR international normalized ratio
IPPB intermittent positive pressure breathing
IU international unit
IV intravenous(ly)
IVU intravenous urography
K potassium
kcal kilocalorie (food calorie)
kg kilogram
L liter
lb pound
LDH lactic dehydrogenase
M molar
m meter
MCH mean corpuscular hemoglobin
MCHC mean corpuscular hemoglobin concentration
mCi millicurie
MCV mean corpuscular volume
mEq milliequivalent
Mg magnesium
mg milligram
MI myocardial infarction
MIC minimum inhibitory concentration
mIU milli-international unit
mL milliliter
mm millimeter
mmol millimole
mo month
mol wt molecular weight
mOsm milliosmole
MRI magnetic resonance imaging
N nitrogen; normal (strength of solution)
Na sodium
NaCl sodium chloride
ng nanogram (= millimicrogram)
nm nanometer (= millimicron)
nmol nanomole
npo nothing by mouth
NSAID nonsteroidal anti-inflammatory drug
O2 oxygen
OTC over-the-counter (pharmaceuticals)
oz ounce
P phosphorus; pressure
PAco2 alveolar carbon dioxide partial pressure
Paco2 arterial carbon dioxide partial pressure
PAo2 alveolar oxygen partial pressure
Pao2arterial oxygen partial pressure
PAS periodic acid-Schiff
Pco2 carbon dioxide partial pressure (or tension)
PCR polymerase chain reaction
PET positron emission tomography
pg picogram (= micromicrogram)
pH hydrogen ion concentration
PMN polymorphonuclear leukocyte
po orally
Po2 oxygen partial pressure (or tension)
PPD purified protein derivative (tuberculin)
ppm parts per million
prn as needed
PT prothrombin time
PTT partial thromboplastin time
q every
qid 4 times a day
RA rheumatoid arthritis
RBC red blood cell
RNA ribonucleic acid
Sao2 arterial oxygen saturation
SBE subacute bacterial endocarditis
sc subcutaneous(ly)
SI International System of Units
SIDS sudden infant death syndrome
SLE systemic lupus erythematosus
soln solution
sp species (singular)
spp species (plural)
sp gr specific gravity
sq square
SSRI selective serotonin reuptake inhibitor
STS serologic test(s) for syphilis
TB tuberculosis
tid 3 times a day
TPN total parenteral nutrition
URI upper respiratory infection
UTI urinary tract infection
WBC white blood cell
WHO World Health Organization
wt weight
μ micro-; micron
μ Ci microcurie
μ g microgram
μ L microliter
μ m micrometer (= micron)
μ mol micromole
μ Osm micro-osmole
m μ millimicron (= nanometer)