Internal Medicine Abbreviations

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Internal Medicine Alphabet – A

S. No	Abbreviation	Full Form	Short Explanation	Practical Example
A001	ABG	Arterial Blood Gas	A test measuring oxygen, carbon dioxide, and pH in arterial blood	ABG is ordered in ICU patients with respiratory distress.
A002	ACE	Angiotensin-Converting Enzyme	An enzyme involved in blood pressure regulation	ACE inhibitors are prescribed for hypertension.
A003	ACEI	Angiotensin-Converting Enzyme Inhibitor	Drugs that block ACE to lower blood pressure	Lisinopril is a commonly used ACEI in heart failure.
A004	ACL	Anterior Cruciate Ligament	A major ligament in the knee joint	ACL tears are common sports injuries.
A005	ACTH	Adrenocorticotropic Hormone	A pituitary hormone stimulating cortisol release	ACTH test is used in adrenal insufficiency evaluation.
A006	AD	Alzheimer’s Disease	A neurodegenerative disorder causing memory loss	Donepezil is used to manage symptoms of AD.
A007	ADA	American Diabetes Association	Professional body setting diabetes care guidelines	ADA recommends HbA1c for diabetes monitoring.
A008	ADH	Antidiuretic Hormone	Hormone regulating water reabsorption in kidneys	ADH deficiency causes diabetes insipidus.
A009	ADHD	Attention Deficit Hyperactivity Disorder	A neurobehavioral disorder with inattention & hyperactivity	Methylphenidate is used in ADHD management.
A010	ADR	Adverse Drug Reaction	Unwanted or harmful effect of a medication	Rash due to penicillin is an ADR.
A011	AFP	Alpha-Fetoprotein	A fetal protein, elevated in some cancers	AFP is elevated in hepatocellular carcinoma.
A012	AIDS	Acquired Immunodeficiency Syndrome	Advanced stage of HIV infection	Opportunistic infections occur in AIDS patients.
A013	AKI	Acute Kidney Injury	Sudden decline in kidney function	Contrast dye can cause AKI.
A014	ALS	Amyotrophic Lateral Sclerosis	Progressive neurodegenerative disorder	ALS presents with muscle weakness and fasciculations.
A015	ALT	Alanine Aminotransferase	Liver enzyme used to assess liver damage	ALT is elevated in hepatitis.
A016	AMI	Acute Myocardial Infarction	Commonly called a heart attack	Troponin test helps diagnose AMI.
A017	ANA	Antinuclear Antibody	Autoantibody test used in autoimmune diseases	Positive ANA in systemic lupus erythematosus.
A018	ANCA	Anti-Neutrophil Cytoplasmic Antibody	Autoantibody linked to vasculitis	c-ANCA is positive in Wegener’s granulomatosis.
A019	ANC	Absolute Neutrophil Count	Indicator of infection risk in patients	Low ANC indicates neutropenia.
A020	AOM	Acute Otitis Media	Middle ear infection	AOM is common in children with ear pain and fever.
A021	AP	Alkaline Phosphatase	Enzyme indicating bone or liver disease	Elevated AP in cholestasis.
A022	APC	Antigen-Presenting Cell	Immune cell presenting antigens to T-cells	Dendritic cells act as APCs.
A023	APL	Acute Promyelocytic Leukemia	Subtype of acute myeloid leukemia	APL is treated with ATRA therapy.
A024	APTT	Activated Partial Thromboplastin Time	Coagulation test for intrinsic pathway	Prolonged APTT in hemophilia.
A025	ARDS	Acute Respiratory Distress Syndrome	Severe lung failure with hypoxemia	ARDS occurs in severe pneumonia and sepsis.
A026	ARF	Acute Renal Failure	Sudden kidney dysfunction	ARF can be caused by dehydration or sepsis.
A027	ARMD	Age-Related Macular Degeneration	Leading cause of blindness in elderly	ARMD leads to central vision loss.
A028	AS	Aortic Stenosis	Narrowing of aortic valve	AS presents with chest pain and syncope.
A029	AST	Aspartate Aminotransferase	Enzyme for liver and heart injury detection	AST is elevated in alcoholic liver disease.
A030	ATN	Acute Tubular Necrosis	Common cause of AKI	ATN results from ischemia or toxins.
A031	ATP	Adenosine Triphosphate	Primary energy carrier in cells	ATP powers muscle contraction.
A032	AV	Atrioventricular	Relating to atrium and ventricle of heart	AV node conducts impulses between atria and ventricles.
A033	AVF	Arteriovenous Fistula	Surgical connection of artery and vein	AVF used in hemodialysis patients.
A034	AVM	Arteriovenous Malformation	Abnormal connection between artery and vein	Brain AVM can cause stroke.
A035	AVR	Aortic Valve Replacement	Surgery for severe aortic stenosis	AVR improves survival in critical AS.
A036	Aβ	Amyloid Beta	Protein implicated in Alzheimer’s disease	Amyloid plaques in brain seen in AD.
A037	ACh	Acetylcholine	Neurotransmitter in CNS and PNS	ACh deficiency in myasthenia gravis.
A038	AChE	Acetylcholinesterase	Enzyme breaking down acetylcholine	AChE inhibitors used in Alzheimer’s disease.
A039	ACR	Albumin-to-Creatinine Ratio	Kidney function marker in urine	ACR elevated in diabetic nephropathy.
A040	ACT	Activated Clotting Time	Test for monitoring heparin therapy	ACT is used in cardiac catheterization.
A041	ADL	Activities of Daily Living	Basic tasks necessary for self-care	ADL assessment used in geriatrics.
A042	AED	Automated External Defibrillator	Portable device to restore heart rhythm	AED used in cardiac arrest emergencies.
A043	AFB	Acid-Fast Bacillus	Bacteria detected in TB testing	AFB smear positive in pulmonary TB.
A044	AFP-L3	AFP-Lens Culinaris Agglutinin	Tumor marker for liver cancer	Used to differentiate benign from malignant liver disease.
A045	AF	Atrial Fibrillation	Irregular heart rhythm	Warfarin prescribed in AF for stroke prevention.
A046	AG	Anion Gap	Electrolyte calculation for metabolic acidosis	Elevated AG in diabetic ketoacidosis.
A047	AI	Aortic Insufficiency	Aortic valve does not close properly	AI causes diastolic murmur.
A048	AIDP	Acute Inflammatory Demyelinating Polyneuropathy	Most common form of Guillain-Barré syndrome	AIDP presents with ascending paralysis.
A049	ALD	Alcoholic Liver Disease	Liver damage due to chronic alcohol use	ALD leads to cirrhosis.
A050	ALP	Alkaline Phosphatase	Enzyme for bone and liver function	Raised ALP in biliary obstruction.
A051	ALPS	Autoimmune Lymphoproliferative Syndrome	Rare immune disorder causing lymphadenopathy	ALPS diagnosed in children with chronic lymphadenopathy.
A052	AML	Acute Myeloid Leukemia	Aggressive blood cancer	AML presents with anemia and bleeding.
A053	AMP	Adenosine Monophosphate	Nucleotide in cellular metabolism	AMP regulates energy homeostasis.
A054	AMS	Altered Mental Status	General term for confusion or reduced alertness	AMS caused by infection, stroke, or hypoglycemia.
A055	ANA IFA	Antinuclear Antibody Indirect Fluorescent Assay	Diagnostic test for autoimmune disease	Positive in lupus and scleroderma.
A056	ANP	Atrial Natriuretic Peptide	Hormone regulating blood pressure and fluid balance	ANP levels rise in heart failure.
A057	Ao	Aorta	Main artery of the body	Ao aneurysm can rupture.
A058	APACHE	Acute Physiology and Chronic Health Evaluation	ICU severity scoring system	APACHE II used to assess mortality risk.
A059	APA	Antiphospholipid Antibody	Autoantibody associated with clotting disorders	APA positive in recurrent miscarriages.
A060	APS	Antiphospholipid Syndrome	Autoimmune clotting disorder	APS patients prone to DVT and stroke.
A061	AR	Aortic Regurgitation	Blood leaks back into left ventricle	AR leads to wide pulse pressure.
A062	ARC	AIDS-Related Complex	Early stage of HIV progression	ARC includes chronic lymphadenopathy.
A063	ARI	Acute Respiratory Infection	Infection of upper/lower respiratory tract	ARI common in children.
A064	ARR	Aldosterone Renin Ratio	Screening test for primary aldosteronism	High ARR in Conn’s syndrome.
A065	ASA	Acetylsalicylic Acid	Commonly known as aspirin	ASA prevents platelet aggregation.
A066	ASD	Atrial Septal Defect	Congenital hole between atria	ASD causes left-to-right shunt.
A067	ASHD	Arteriosclerotic Heart Disease	Heart disease due to atherosclerosis	ASHD is a major cause of angina.
A068	ASO	Antistreptolysin O	Antibody test for recent streptococcal infection	Elevated ASO in rheumatic fever.
A069	AT	Antithrombin	Protein that prevents blood clotting	AT deficiency leads to thrombosis.
A070	ATA	American Thyroid Association	Organization for thyroid disease management	ATA guidelines used in thyroid cancer.
A071	ATD	Anti-Thyroid Drug	Medications to treat hyperthyroidism	Methimazole is an ATD.
A072	ATPase	Adenosine Triphosphatase	Enzyme regulating ATP breakdown	Na⁺/K⁺ ATPase maintains cell balance.
A073	ATLS	Advanced Trauma Life Support	Protocol for trauma management	ATLS followed in ER trauma care.
A074	AVB	Atrioventricular Block	Conduction block between atria & ventricles	AVB diagnosed on ECG.
A075	AVN	Avascular Necrosis	Bone death due to loss of blood supply	AVN common in hip after steroid use.
A076	AVP	Arginine Vasopressin	Another name for ADH	AVP analogs used in diabetes insipidus.
A077	Ax	Axilla	Medical term for armpit	Lymph nodes in Ax examined in breast cancer.
A078	AZT	Azidothymidine (Zidovudine)	Antiretroviral drug for HIV	AZT prevents mother-to-child HIV transmission.
A079	Aα	Alpha Alpha Fibers	Nerve fibers for muscle control	Aα fibers mediate reflexes.
A080	Aδ	Alpha Delta Fibers	Nerve fibers carrying pain signals	Aδ fibers transmit sharp pain.
A081	AGA	Appropriate for Gestational Age	Refers to newborns with normal growth	AGA infants have lower complications.
A082	AGN	Acute Glomerulonephritis	Inflammation of glomeruli in kidneys	AGN after streptococcal infection.
A083	AGS	Acute Gastroenteritis Syndrome	Infection causing vomiting & diarrhea	AGS common in viral GI infections.
A084	AIHA	Autoimmune Hemolytic Anemia	Body attacks its own RBCs	AIHA treated with steroids.
A085	AIN	Acute Interstitial Nephritis	Inflammation of kidney interstitium	AIN caused by drug hypersensitivity.
A086	AIP	Acute Intermittent Porphyria	Rare metabolic disorder	AIP presents with abdominal pain and neuropathy.
A087	AIT	Autoimmune Thyroiditis	Thyroid inflammation due to autoimmunity	Hashimoto’s thyroiditis is an AIT.
A088	AIVR	Accelerated Idioventricular Rhythm	Benign arrhythmia seen post-MI	AIVR usually resolves without treatment.
A089	ALAT	Alanine Aminotransferase	Same as ALT, liver enzyme	Elevated in hepatitis.
A090	ALKP	Alkaline Phosphatase	Same as ALP, enzyme	Elevated in bone disorders.
A091	ALL	Acute Lymphoblastic Leukemia	Cancer of immature lymphocytes	ALL common in children.
A092	ALPPS	Associating Liver Partition and Portal vein ligation for Staged hepatectomy	Surgical procedure for liver tumors	ALPPS done in hepatocellular carcinoma.
A093	ALSFRS	ALS Functional Rating Scale	Scale for ALS severity	Used to monitor ALS progression.
A094	AMAN	Acute Motor Axonal Neuropathy	Subtype of Guillain-Barré syndrome	AMAN presents with acute paralysis.
A095	AMN	Adrenomyeloneuropathy	Genetic disorder linked to adrenal insufficiency	AMN causes spastic paraparesis.
A096	AMP	Amphetamine	CNS stimulant drug	Used in ADHD management.
A097	AMR	Antimicrobial Resistance	Resistance of microbes to antibiotics	AMR is a global health concern.
A098	ANA	Anti-Nuclear Antibodies	Autoantibodies against nuclear material	ANA test positive in lupus.
A099	ANF	Atrial Natriuretic Factor	Similar to ANP hormone	ANF lowers blood pressure.
A100	ANI	Acute Neurological Injury	Sudden damage to the brain or spinal cord	ANI caused by trauma or stroke.
A101	ANS	Autonomic Nervous System	Controls involuntary functions	ANS dysfunction in diabetes.
A102	AoD	Aneurysm of Aorta	Localized dilatation of aorta	AoD rupture causes sudden death.
A103	APD	Automated Peritoneal Dialysis	Home-based dialysis technique	APD used in chronic kidney disease.
A104	APE	Acute Pulmonary Edema	Fluid accumulation in lungs	APE seen in left heart failure.
A105	API	Acute Pancreatitis Index	Scoring system for severity	API guides treatment.
A106	APOE	Apolipoprotein E	Protein linked to Alzheimer’s risk	APOE4 allele increases AD risk.
A107	APP	Acute Phase Proteins	Proteins rising in inflammation	CRP is an APP.
A108	APRV	Airway Pressure Release Ventilation	Ventilation strategy in ARDS	APRV improves oxygenation.
A109	ARB	Angiotensin Receptor Blocker	Antihypertensive medication	Losartan is a common ARB.
A110	ARC	Acute Renal Colic	Severe flank pain due to kidney stones	ARC treated with NSAIDs.
A111	AREDS	Age-Related Eye Disease Study	Clinical trial on vitamins for ARMD	AREDS formula used in eye supplements.
A112	ARF	Acute Rheumatic Fever	Post-strep autoimmune disease	ARF causes carditis and arthritis.
A113	ARG	Arginine	Amino acid in protein metabolism	ARG used in nitric oxide synthesis.
A114	ARI	Acute Respiratory Insufficiency	Inadequate breathing function	ARI may need mechanical ventilation.
A115	ARR	Annualized Relapse Rate	Measure in multiple sclerosis trials	ARR used in MS drug studies.
A116	ARS	Acute Radiation Syndrome	Illness after high radiation exposure	ARS seen in nuclear accidents.
A117	ART	Antiretroviral Therapy	HIV treatment using drug combinations	ART improves survival in HIV/AIDS.
A118	ASAT	Aspartate Aminotransferase	Same as AST enzyme	Used in liver tests.
A119	ASB	Asymptomatic Bacteriuria	Presence of bacteria in urine without symptoms	ASB treated in pregnancy.
A120	ASCVD	Atherosclerotic Cardiovascular Disease	Heart disease due to atherosclerosis	Statins prescribed in ASCVD.
A121	ASH	American Society of Hematology	Professional hematology body	ASH publishes blood disease guidelines.
A122	ASL	Arterial Spin Labeling	MRI perfusion technique	Used in stroke imaging.
A123	ASM	Antiseizure Medication	Drugs preventing seizures	Valproate is an ASM.
A124	ASO	Anti-Streptolysin O	Test for strep infection	Elevated in post-strep complications.
A125	ASP	Aspiration Pneumonia	Lung infection from aspirated material	Seen in stroke patients.
A126	AST	Aspartate Transaminase	Same as AST enzyme	Elevated in hepatitis.
A127	AT	Atrial Tachycardia	Rapid rhythm from atrium	Treated with beta-blockers.
A128	ATA	American Thoracic Association	Lung-focused medical body	ATA issues COPD guidelines.
A129	ATC	Around The Clock	Continuous drug dosing schedule	Morphine given ATC for pain.
A130	ATG	Anti-Thymocyte Globulin	Immunosuppressive agent	ATG used in transplant rejection.
A131	ATL	Adult T-cell Leukemia	Cancer linked to HTLV-1 virus	ATL occurs in endemic regions.
A132	ATM	Ataxia Telangiectasia Mutated	Gene involved in DNA repair	ATM mutations increase cancer risk.
A133	ATP7B	ATPase Copper Transporting Beta	Gene mutated in Wilson’s disease	ATP7B testing confirms diagnosis.
A134	ATR	Atrial Rate	ECG measurement of atrial rhythm	ATR high in supraventricular tachycardia.
A135	ATS	American Thoracic Society	Respiratory medicine authority	ATS guidelines used in TB care.
A136	ATT	Anti-Tuberculosis Therapy	Treatment for TB infection	ATT includes isoniazid and rifampicin.
A137	ATV	Atazanavir	Antiretroviral drug for HIV	ATV used in ART regimens.
A138	AU	Arbitrary Units	Lab measurement unit	Hormone levels expressed in AU.
A139	AUC	Area Under Curve	Pharmacokinetics measure	AUC guides drug dosing.
A140	AUE	Acute Uremic Encephalopathy	Brain dysfunction due to uremia	AUE requires urgent dialysis.
A141	AUR	Acute Urinary Retention	Sudden inability to urinate	AUR seen in prostate enlargement.
A142	AUS	Atypical Urothelial Cells	Cytology term for urine abnormalities	AUS may need cystoscopy.
A143	AV	Aortic Valve	Valve between LV and aorta	AV stenosis requires replacement.
A144	AVH	Auditory Verbal Hallucination	Hearing voices without external source	AVH common in schizophrenia.
A145	AVNRT	AV Nodal Reentrant Tachycardia	Common supraventricular arrhythmia	AVNRT treated with adenosine.
A146	AVP	Atrioventricular Pacing	Pacemaker setting for AV rhythm	AVP used in bradycardia.
A147	AVR	Aortic Valve Replacement	Surgery for diseased aortic valve	AVR done via TAVR or open-heart.
A148	AVS	Adrenal Vein Sampling	Test for source of aldosterone excess	AVS differentiates unilateral vs bilateral hyperaldosteronism.
A149	AVSD	Atrioventricular Septal Defect	Congenital defect in atrioventricular septum	AVSD seen in Down syndrome.
A150	AVWS	Acquired Von Willebrand Syndrome	Acquired bleeding disorder	AVWS linked to heart disease.
A151	AXR	Abdominal X-Ray	Imaging for bowel obstruction, perforation	AXR shows air-fluid levels.
A152	AZA	Azathioprine	Immunosuppressant drug	AZA used in autoimmune diseases.
A153	AβPP	Amyloid Beta Precursor Protein	Protein in Alzheimer’s disease	APP mutations linked to AD.
A154	A-β	Alpha-Beta Fibers	Nerve fibers carrying touch signals	Aβ fibers transmit vibration.
A155	A-CVR	Adjusted Cardiovascular Risk	Clinical risk score	Used in preventive cardiology.
A156	A1AT	Alpha-1 Antitrypsin	Enzyme deficiency causing lung & liver disease	A1AT deficiency causes emphysema.
A157	A1C	Hemoglobin A1C	Long-term glucose control marker	A1C > 6.5% diagnostic for diabetes.
A158	A2M	Alpha-2 Macroglobulin	Protein in plasma protease inhibition	A2M elevated in nephrotic syndrome.
A159	A4	Apolipoprotein A4	Protein in lipid metabolism	A4 linked to atherosclerosis.
A160	AAD	Antibiotic-Associated Diarrhea	Diarrhea caused by antibiotic use	C. difficile common cause.
A161	AAC	Acute Acalculous Cholecystitis	Gallbladder inflammation without stones	AAC seen in ICU patients.
A162	AAG	Autoimmune Autonomic Ganglionopathy	Rare autoimmune neuropathy	Causes orthostatic hypotension.
A163	AAI	Atrial Asynchronous Inhibited Pacemaker	Pacemaker setting	Used in arrhythmia patients.
A164	AAL	Amino Acid Level	Lab measurement for amino acid disorders	AAL used in metabolic diseases.
A165	AAM	Acute Aortic Murmur	Murmur from aortic valve disease	AAM detected on auscultation.
A166	AAP	Acute Abdominal Pain	Symptom with many causes	AAP requires urgent evaluation.
A167	AAR	Age-Adjusted Rate	Epidemiological measure	Used in population health.
A168	AASLD	American Association for Study of Liver Diseases	Hepatology authority	Publishes cirrhosis guidelines.
A169	AAV	Anti-Neutrophil Cytoplasmic Antibody Associated Vasculitis	Autoimmune vasculitis	AAV includes GPA, MPA.
A170	AAW	Abdominal Aortic Aneurysm Wall	Refers to vessel wall thickness	Monitored in aneurysm imaging.
A171	ABVD	Adriamycin, Bleomycin, Vinblastine, Dacarbazine	Chemotherapy regimen for Hodgkin lymphoma	ABVD used as first-line treatment.
A172	AC	Acromioclavicular	Joint between clavicle and acromion	AC joint dislocation common in trauma.
A173	ACA	Anterior Cerebral Artery	Brain artery supplying frontal lobes	ACA stroke causes leg weakness.
A174	ACC	American College of Cardiology	Professional cardiology body	ACC issues heart disease guidelines.
A175	ACE2	Angiotensin-Converting Enzyme 2	Receptor for SARS-CoV-2 virus	ACE2 key in COVID-19 infection.
A176	ACLF	Acute-on-Chronic Liver Failure	Sudden worsening of chronic liver disease	ACLF carries high mortality.
A177	ACM	Acute Coronary Syndrome Management	Protocol for ACS	Includes PCI, thrombolysis.
A178	ACS	Acute Coronary Syndrome	Spectrum of heart attacks	ACS includes STEMI, NSTEMI.
A179	ACTH Stimulation Test	Adrenocorticotropic Hormone Stimulation Test	Evaluates adrenal function	Used in Addison’s disease.
A180	ADA-SCID	Adenosine Deaminase Severe Combined Immunodeficiency	Genetic immune disorder	ADA-SCID treated with gene therapy.
A181	ADCC	Antibody-Dependent Cellular Cytotoxicity	Immune defense mechanism	ADCC used in cancer immunotherapy.
A182	ADEM	Acute Disseminated Encephalomyelitis	Post-infection demyelinating disease	ADEM seen after viral illness.
A183	ADMA	Asymmetric Dimethylarginine	Endogenous NOS inhibitor	Elevated ADMA linked to heart disease.
A184	AEC	Absolute Eosinophil Count	Lab test for allergies, parasites	High AEC in asthma.
A185	AEDH	Acute Extradural Hematoma	Blood collection between skull & dura	AEDH after head injury.
A186	AFI	Amniotic Fluid Index	Ultrasound measure in pregnancy	Low AFI indicates oligohydramnios.
A187	AGI	Acute Gastrointestinal Bleed	GI bleeding requiring urgent care	AGI presents with melena or hematemesis.
A188	AHI	Apnea Hypopnea Index	Measure of sleep apnea severity	AHI > 30 indicates severe OSA.
A189	AIx	Augmentation Index	Measure of arterial stiffness	Used in hypertension studies.
A190	ALDH	Aldehyde Dehydrogenase	Enzyme in alcohol metabolism	ALDH deficiency causes flushing.
A191	ALK	Anaplastic Lymphoma Kinase	Gene in certain cancers	ALK inhibitors used in lung cancer.
A192	ALT	Alternative Therapy	Non-mainstream medical practice	ALT includes herbal medicine.
A193	AMPK	AMP-Activated Protein Kinase	Energy-sensing enzyme	AMPK regulates metabolism.
A194	AMY	Amylase	Digestive enzyme for carbohydrates	Elevated in pancreatitis.
A195	ANA-HEp2	ANA Hep-2 Cell Line Test	Gold standard for ANA testing	Used in lupus diagnosis.
A196	ANPRA	Acute Non-Proliferative Retinopathy	Early stage diabetic eye disease	ANPRA seen in diabetes.
A197	AOC	Acute Obstructive Colitis	Blockage of colon causing inflammation	Requires urgent surgery.
A198	AOMT	Acute Otomastoiditis	Complication of middle ear infection	AOMT requires antibiotics.
A199	AOP	Apnea of Prematurity	Breathing pauses in premature infants	AOP managed with caffeine therapy.
A200	APAF	Atrial Preference Algorithm Function	Pacemaker algorithm for rhythm control	APAF reduces atrial arrhythmias.