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 – N

S. No	Abbreviation	Full Form	Short Explanation	Practical Example
N001	NA	Sodium (Natrium)	Key electrolyte in fluid balance.	Hyponatremia in SIADH.
N002	NABP	National Association of Boards of Pharmacy	US body regulating pharmacy practice.	Oversees NAPLEX licensing exam.
N003	NAC	N-Acetylcysteine	Antidote for acetaminophen toxicity, mucolytic.	Used in Tylenol overdose.
N004	NAD	Nicotinamide Adenine Dinucleotide	Cellular redox cofactor.	Target in metabolism studies.
N005	NAE	Net Acid Excretion	Kidney measure of acid excretion.	Low in renal tubular acidosis.
N006	NAFLD	Non-Alcoholic Fatty Liver Disease	Fat accumulation in liver without alcohol.	Common in obesity.
N007	NASH	Non-Alcoholic Steatohepatitis	Progressive form of NAFLD.	Can progress to cirrhosis.
N008	NAT	Nucleic Acid Test	Diagnostic test detecting viral/bacterial DNA or RNA.	Used in HIV, HCV diagnosis.
N009	NAV	Neurovascular Bundle	Nerve-artery-vein grouping.	Risk during surgery.
N010	NB	Newborn / Nota Bene	Used in pediatrics or medical notes.	“NB: patient allergic to penicillin.”
N011	NBC	Non-Bacterial Cystitis	Bladder inflammation without infection.	Seen in interstitial cystitis.
N012	NBM	Nil By Mouth	Pre-op order for patients.	Written on charts before surgery.
N013	NBN	Neonatal Brachial Plexus Neuropathy	Birth-related nerve injury.	Causes arm weakness in infants.
N014	NBS	Newborn Screening	Neonatal tests for genetic/metabolic diseases.	PKU screening.
N015	NC	Nasal Cannula	Device for oxygen delivery.	Used in hypoxemia.
N016	NCA	Neurogenic Claudication	Leg pain due to spinal stenosis.	Improves with sitting/flexion.
N017	NCC	Neurocysticercosis	Parasitic brain infection.	Seizure common presentation.
N018	NCD	Non-Communicable Disease	Chronic disease category.	Diabetes, hypertension.
N019	NCEP	National Cholesterol Education Program	US guideline committee.	Issues cholesterol management targets.
N020	NCV	Nerve Conduction Velocity	Nerve function test.	Reduced in peripheral neuropathy.
N021	ND	Nasoduodenal Tube	Feeding tube reaching duodenum.	Used in aspiration risk patients.
N022	NDA	New Drug Application	FDA drug approval process.	Required before market release.
N023	NDD	Neurodegenerative Disorder	Disorders causing progressive neuronal loss.	Includes Alzheimer’s, Parkinson’s.
N024	NDI	Nephrogenic Diabetes Insipidus	Kidney unresponsive to ADH.	Causes polyuria, polydipsia.
N025	NDMA	N-Nitrosodimethylamine	Carcinogenic contaminant.	Found in recalled medications.
N026	NE	Norepinephrine	Adrenergic neurotransmitter, vasopressor.	Used in septic shock.
N027	NEAD	Non-Epileptic Attack Disorder	Seizure-like psychogenic episodes.	Differentiated from epilepsy.
N028	NEC	Necrotizing Enterocolitis	Severe neonatal bowel disease.	Common in preterm infants.
N029	NED	No Evidence of Disease	Cancer follow-up status.	Used in oncology records.
N030	NEP	Neutral Endopeptidase	Enzyme degrading natriuretic peptides.	Target for heart failure drugs.
N031	NES	Night Eating Syndrome	Eating disorder with nocturnal intake.	Managed with CBT.
N032	NET	Neuroendocrine Tumor	Tumor of neuroendocrine origin.	Includes carcinoid tumors.
N033	NEXUS	National Emergency X-Radiography Utilization Study	Criteria for clearing cervical spine.	Used in trauma care.
N034	NF	Neurofibromatosis	Genetic tumor disorder.	NF1 causes café-au-lait spots.
N035	NFG	Non-Fasting Glucose	Blood sugar without fasting.	Used in diabetes screening.
N036	NFR	Non-Fatal Recurrence	Medical outcome reporting.	Used in oncology follow-up.
N037	NFT	Neurofibrillary Tangles	Alzheimer’s pathology marker.	Seen on brain histology.
N038	NFU	National Formulary Update	Drug formulary listing.	Used in hospital pharmacies.
N039	NG	Nasogastric Tube	Tube placed into stomach.	Used for decompression or feeding.
N040	NGC	Next Generation Sequencing	Advanced genetic sequencing.	Used in oncology genomics.
N041	NGT	Nasogastric Tube Feeding	Nutritional support method.	Used in stroke patients.
N042	NH	Nursing Home	Long-term care facility.	Elderly patient placement.
N043	NHC	National Health Commission (China)	Regulatory authority.	Issued COVID-19 protocols.
N044	NHI	National Health Insurance	Universal healthcare scheme.	Common in Asian countries.
N045	NHL	Non-Hodgkin Lymphoma	Lymphoid malignancy.	Treated with rituximab.
N046	NHMRC	National Health and Medical Research Council	Australian medical body.	Funds clinical trials.
N047	NHP	Non-Human Primate	Research model.	Used in vaccine development.
N048	NHS	National Health Service (UK)	UK public healthcare system.	Provides universal coverage.
N049	NHT	Non-Hormonal Therapy	Alternative to HRT.	Used in menopause.
N050	NHYA	New York Heart Association	Heart failure classification system.	Class III: symptoms on mild exertion.
N051	NIC	Neonatal Intensive Care	Specialized newborn care.	NICU for premature infants.
N052	NID	Non-Insulin Dependent Diabetes	Old term for type 2 DM.	Managed with lifestyle + meds.
N053	NIDDM	Non-Insulin Dependent Diabetes Mellitus	Type 2 diabetes.	Most common diabetes form.
N054	NIF	Negative Inspiratory Force	Respiratory muscle strength measure.	Used in neuromuscular disease.
N055	NIL	No Initial Lesion	Radiology note.	Appears in fracture reports.
N056	NIMH	National Institute of Mental Health	US research institute.	Supports psychiatric studies.
N057	NIMS	National Incident Management System	US disaster response system.	Applied during pandemics.
N058	NINDS	National Institute of Neurological Disorders and Stroke	US NIH branch.	Funds stroke research.
N059	NIPT	Non-Invasive Prenatal Testing	Screening test from maternal blood.	Detects Down syndrome.
N060	NIR	Near-Infrared Spectroscopy	Noninvasive oxygenation imaging.	Used in brain monitoring.

S. No	Abbreviation	Full Form	Short Explanation	Practical Example
N061	NIRS	Near-Infrared Spectroscopy	Non-invasive monitoring of tissue oxygenation.	Used in ICU for cerebral perfusion monitoring.
N062	NIS	National Inpatient Sample	Large US hospitalization database.	Used for epidemiological studies.
N063	NIV	Non-Invasive Ventilation	Ventilation support without intubation.	Used in COPD exacerbations.
N064	NKA	No Known Allergies	Common chart notation.	“NKA to drugs” written in records.
N065	NKDA	No Known Drug Allergies	Allergy history abbreviation.	Written in prescription notes.
N066	NK	Natural Killer (Cell)	Immune cells for tumor/virus control.	Measured in immunology studies.
N067	NKT	Natural Killer T-cell	Immune cell subtype.	Involved in autoimmunity.
N068	NL	Normal Limits	Reference for lab values.	“Electrolytes WNL” in reports.
N069	NLM	National Library of Medicine	US medical knowledge repository.	Hosts PubMed.
N070	NLR	Neutrophil-to-Lymphocyte Ratio	Inflammation marker.	Elevated in sepsis.
N071	NLT	Nasolacrimal Tube	Used in ophthalmology.	For blocked tear ducts.
N072	NM	Nuclear Medicine	Imaging using radioactive tracers.	PET, SPECT scans.
N073	NMA	Non-Medical Attendant	Caregiver in hospital setting.	Registered for patient assistance.
N074	NMB	Neuromuscular Blockade	Paralysis induced in anesthesia.	Rocuronium used in intubation.
N075	NMD	Neuromuscular Disease	Disorders affecting muscles/nerves.	Includes ALS, myopathy.
N076	NME	Necrolytic Migratory Erythema	Rash associated with glucagonoma.	Seen in rare pancreatic tumors.
N077	NMES	Neuromuscular Electrical Stimulation	Rehab technique using electrical current.	Used after stroke.
N078	NMF	Non-Melanoma Skin Cancer	Includes BCC, SCC.	Common skin malignancies.
N079	NMI	Non–Mass-Forming Infiltration	Radiology finding.	Seen in breast imaging.
N080	NML	Normal	Abbreviation in notes/reports.	“Liver enzymes NML.”
N081	NMO	Neuromyelitis Optica	Autoimmune demyelinating disorder.	Causes optic neuritis + myelitis.
N082	NMP	Nuclear Magnetic Resonance Spectroscopy (Medical Physics)	Used in metabolic imaging.	Brain spectroscopy in tumors.
N083	NMS	Neuroleptic Malignant Syndrome	Life-threatening reaction to antipsychotics.	Rigidity, fever, altered sensorium.
N084	NMU	Non-Medical Use (of drugs)	Misuse of prescription medications.	Benzodiazepine abuse.
N085	NN	Neonate	Newborn child <28 days.	NICU admissions coded as NN.
N086	NNH	Number Needed to Harm	Harm risk measure in clinical trials.	NNH = 50 for GI bleed risk.
N087	NNT	Number Needed to Treat	Effectiveness measure in trials.	NNT = 20 for statins.
N088	NO	Nitric Oxide	Vasodilator gas molecule.	Used in pulmonary hypertension.
N089	NOAC	Non-Vitamin K Oral Anticoagulant	Newer anticoagulants.	Includes apixaban, rivaroxaban.
N090	NOC	Nursing Outcomes Classification	Standardized nursing outcomes.	Used in care planning.
N091	NOF	Neck of Femur (fracture)	Common fracture site in elderly.	Managed with hip replacement.
N092	NOI	Not Otherwise Indicated	Used in pathology/diagnosis.	“Sarcoma NOI.”
N093	NOP	Nothing by Oral Route	Pre-op fasting order.	Written in peri-op notes.
N094	NOS	Not Otherwise Specified	Nonspecific diagnosis category.	“Pneumonia NOS.”
N095	NOTS	Non-Operative Treatment Strategy	Conservative care approach.	Used in orthopedic fractures.
N096	NP	Nurse Practitioner	Advanced practice registered nurse.	Prescribes medications.
N097	NPA	Nasopharyngeal Aspirate	Diagnostic specimen.	Used in viral respiratory infections.
N098	NPC	Nasopharyngeal Carcinoma	Head and neck cancer.	Associated with EBV.
N099	NPH	Neutral Protamine Hagedorn Insulin	Intermediate-acting insulin.	Used in type 1 diabetes.
N100	NPI	National Provider Identifier	US physician identifier.	Used in billing.
N101	NPO	Nil Per Os (Nothing by Mouth)	Standard fasting order.	NPO before anesthesia.
N102	NPP	Non-Physician Provider	Includes PAs, NPs.	Expands care delivery.
N103	NPV	Negative Predictive Value	Diagnostic test measure.	High in screening tests.
N104	NR	No Response / Normal Range	Used in test reports.	“Antibody titer NR.”
N105	NRA	No Known Risk Factors	Risk assessment finding.	“MI in patient NRA.”
N106	NRBC	Nucleated Red Blood Cell	Immature RBCs in blood.	Seen in bone marrow stress.
N107	NRC	Nuclear Regulatory Commission	US body overseeing radioisotopes.	Regulates nuclear medicine.
N108	NREM	Non-Rapid Eye Movement Sleep	Sleep stage classification.	NREM deficiency → fatigue.
N109	NRI	Norepinephrine Reuptake Inhibitor	Antidepressant drug class.	Reboxetine is an NRI.
N110	NRN	Neonatal Resuscitation Nurse	Specialized neonatal nurse.	Works in delivery room.
N111	NRS	Numeric Rating Scale	Pain assessment tool (0–10).	Used in chronic pain clinics.
N112	NS	Normal Saline	0.9% sodium chloride solution.	IV fluid of choice in dehydration.
N113	NSA	Non-Steroidal Anti-inflammatory Agent	Analgesic/anti-inflammatory drugs.	Ibuprofen, naproxen.
N114	NSAI	Non-Specific Airway Inflammation	Respiratory pathology finding.	Seen in asthma.
N115	NSCLC	Non-Small Cell Lung Cancer	Most common lung cancer type.	Treated with targeted therapy.
N116	NSD	Normal Spontaneous Delivery	Vaginal delivery without intervention.	Recorded in obstetrics notes.
N117	NSE	Neuron-Specific Enolase	Tumor/cell damage marker.	Elevated in small-cell lung cancer.
N118	NSF	Nephrogenic Systemic Fibrosis	Rare condition in CKD with gadolinium exposure.	Seen in MRI contrast use.
N119	NSIAD	Nephrogenic Syndrome of Inappropriate Antidiuresis	Genetic disorder mimicking SIADH.	Causes hyponatremia.
N120	NSR	Normal Sinus Rhythm	Normal ECG finding.	Written in cardiology reports.
N121	NSS	Normal Saline Solution	IV fluid abbreviation.	NSS 500 mL given stat.
N122	NST	Non-Stress Test (Fetal)	Obstetric fetal monitoring test.	Used in pregnancy checkups.
N123	NSTEMI	Non-ST-Elevation Myocardial Infarction	Type of MI without ST elevation.	Managed with anticoagulation + PCI.
N124	NT	Neurotensin / Nuchal Translucency	Hormone or prenatal ultrasound marker.	NT increased in Down syndrome.
N125	NTA	Nephrotoxic Agent	Drug toxic to kidneys.	Aminoglycosides.
N126	NTCP	Sodium Taurocholate Cotransporting Polypeptide	Liver bile acid transporter.	Target in hepatitis B research.
N127	NTD	Neural Tube Defect	Birth defect of CNS.	Spina bifida, anencephaly.
N128	NTE	Neurotoxic Esterase	Enzyme inhibited in organophosphate poisoning.	Used in toxicology studies.
N129	NTM	Non-Tuberculous Mycobacteria	Opportunistic pathogens.	MAC infection in HIV.
N130	NTP	National Toxicology Program	US toxicology research program.	Evaluates carcinogens.
N131	NTR	No Tumor Recurrence	Oncology follow-up term.	“Patient in NTR status.”
N132	NTS	Nucleus Tractus Solitarius	Brainstem autonomic nucleus.	Involved in BP control.
N133	NTT	Nasotracheal Tube	Used in airway management.	Inserted in facial trauma.
N134	NTX	N-Telopeptide	Bone resorption marker.	Used in osteoporosis monitoring.
N135	NU	Nursing Unit	Hospital floor/ward.	“Pt admitted to NU-4.”
N136	NUA	No Urinary Abnormality	Lab result.	“UA: NUA.”
N137	NUB	Neuro-Urology Board	Specialist group.	Certifies subspecialists.
N138	NUC	Nuclear Cardiology	Nuclear imaging for heart.	Myocardial perfusion scans.
N139	NUD	Non-Ulcer Dyspepsia	Functional dyspepsia.	Common GI complaint.
N140	NUR	Nurse	Common abbreviation.	Appears in staffing notes.
N141	NUS	National University of Singapore (Medicine)	Academic abbreviation.	Appears in med research papers.
N142	NVC	Neurovascular Conflict	Artery compressing cranial nerve.	Seen in trigeminal neuralgia.
N143	NVD	Nausea, Vomiting, Diarrhea	GI symptom triad.	Noted in infectious gastroenteritis.
N144	NVE	Native Valve Endocarditis	Endocarditis in natural heart valve.	Seen with Strep viridans.
N145	NVG	Neovascular Glaucoma	Severe eye disease with new vessel growth.	Associated with diabetes.
N146	NVH	No Visible Hematuria	Urinalysis finding.	“UA: NVH.”
N147	NVL	No Visual Loss	Ophthalmology exam finding.	“Glaucoma screening: NVL.”
N148	NVN	No Vital Needs	ICU/triage note.	Used in disaster medicine.
N149	NVP	Nausea and Vomiting in Pregnancy	Common first-trimester symptom.	Managed with doxylamine.
N150	NVS	Neuro-Vascular Status	Exam finding in trauma.	“NVS intact” in fracture patient.
N151	NWB	Non-Weight Bearing	Orthopedic instruction.	Post-op fracture care.
N152	NWMH	Northwestern Memorial Hospital	US academic hospital.	Appears in research citations.
N153	NWP	No Witnessed Pulse	Cardiac arrest note.	Documented in code events.
N154	NYBC	New York Blood Center	Blood services provider.	Source of transfusion products.
N155	NYC	New York City Department of Health (context)	Appears in epidemiology reports.	COVID-19 NYC data.
N156	NYD	Not Yet Diagnosed	Interim diagnosis status.	“Fever NYD” in ER chart.
N157	NYHA	New York Heart Association	Functional classification of heart failure.	Class II: symptoms on exertion.
N158	NYP	New York-Presbyterian Hospital	Major US medical center.	Appears in clinical trials.
N159	NYS	New York State Department of Health	Regional medical authority.	Licenses physicians.
N160	NZB	New Zealand Blood Service	National transfusion service.	Provides donor blood.
N161	NZO	New Zealand Obesity Study	Epidemiology research project.	Published in medical journals.
N162	N2O	Nitrous Oxide	Anesthetic and analgesic gas.	Used in dental sedation.
N163	N3	Stage N3 Sleep	Deep slow-wave sleep stage.	Critical for memory consolidation.
N164	N4	Stage N4 Sleep (obsolete term)	Now merged with N3.	Historical classification.
N165	N95	N95 Respirator Mask	Protective mask filtering ≥95% airborne particles.	Used in infection control.
N166	N2	Nitrogen Gas	Inert gas in physiology.	Seen in decompression sickness.
N167	N1	Stage N1 Sleep	Lightest sleep stage.	Transition from wakefulness.
N168	N2H4	Hydrazine (toxic compound)	Industrial toxin causing organ damage.	Seen in toxicology cases.
N169	N3H	Third Nerve Palsy (Ophthalmology code)	Neurological deficit.	Causes ptosis, diplopia.
N170	N4H	Fourth Nerve Palsy	Eye movement disorder.	Causes vertical diplopia.
N171	N5	Fifth Cranial Nerve (Trigeminal)	Sensory nerve of face.	Neuralgia causes severe pain.
N172	N6	Sixth Cranial Nerve (Abducens)	Controls lateral rectus muscle.	Palsy → diplopia.
N173	N7	Seventh Cranial Nerve (Facial)	Motor and sensory nerve.	Bell’s palsy affects it.
N174	N8	Eighth Cranial Nerve (Vestibulocochlear)	Hearing and balance.	Vestibular neuritis causes vertigo.
N175	N9	Ninth Cranial Nerve (Glossopharyngeal)	Taste and pharyngeal sensation.	Involved in swallowing reflex.
N176	N10	Tenth Cranial Nerve (Vagus)	Parasympathetic control.	Stimulated in vagus nerve therapy.
N177	N11	Eleventh Cranial Nerve (Accessory)	Shoulder muscle control.	Tested by shrugging.
N178	N12	Twelfth Cranial Nerve (Hypoglossal)	Tongue motor nerve.	Lesion → tongue deviation.
N179	NALT	Nasal-Associated Lymphoid Tissue	Mucosal immune tissue.	First defense in airway infections.
N180	NBI	Narrow Band Imaging	Endoscopic technique to enhance mucosal patterns.	Used in GI endoscopy.
N181	NCL	Neuronal Ceroid Lipofuscinosis	Rare neurodegenerative disease.	Causes childhood dementia.
N182	NIFTP	Non-Invasive Follicular Thyroid Neoplasm with Papillary-like Features	Low-risk thyroid tumor category.	Reduces overtreatment.
N183	NMO-IgG	Neuromyelitis Optica Antibody	Diagnostic antibody.	Positive in Devic’s disease.
N184	NTRK	Neurotrophic Tyrosine Receptor Kinase	Gene involved in cancers.	Target for TRK inhibitors.
N185	NVAF	Non-Valvular Atrial Fibrillation	AF without valve disease.	Indication for NOACs.
N186	NVD (Ophth.)	Neovascularization of the Disc	Eye finding in diabetic retinopathy.	Indicates severe ischemia.
N187	NVE (Eye)	Neovascularization Elsewhere	Retinal vascular growth outside disc.	Marker of proliferative DR.
N188	NGAL	Neutrophil Gelatinase-Associated Lipocalin	Early AKI biomarker.	Elevated after contrast exposure.
N189	NMSK	Neuromusculoskeletal Medicine	Osteopathic specialty.	Used in rehab settings.
N190	NTRX	Neurotoxin Receptor	Receptor bound by toxins.	Used in neuropharmacology.
N191	NPD	Narcissistic Personality Disorder	Psychiatric condition.	Diagnosed with DSM-5.
N192	NSSI	Non-Suicidal Self-Injury	Psychiatric behavioral diagnosis.	Cutting, burning behavior.
N193	NPDES	National Pollutant Discharge Elimination System (toxicology context)	Links to environmental medicine.	Used in lead/arsenic exposure.
N194	NRAS	Neuroblastoma RAS Gene	Mutated in cancers.	Target for precision oncology.
N195	NIS4	NAFLD Fibrosis Score (biomarker panel)	Diagnostic score for NASH.	Used in hepatology.
N196	NRG	Neuregulin	Growth factor in cardiology.	Studied in heart failure recovery.
N197	NOD	Non-Obese Diabetic (mouse model)	Used in diabetes research.	Preclinical autoimmune model.
N198	NPY	Neuropeptide Y	Neurotransmitter in appetite regulation.	Target for obesity research.
N199	NLRP3	NOD-Like Receptor Protein 3 Inflammasome	Mediator of inflammation.	Target in gout therapy.
N200	NRXN	Neurexin	Synaptic protein linked to autism.	Studied in neuropsychiatry.