List of medical abbreviations: I

• I&D - Incision and drainage: a minor surgical procedure to release pus or pressure built up under the skin, such as from an abscess or boil.
• I&O - Intake and output: a record used to monitor the fluid balance of a patient.
• IA - Intra-arterial: administration of medication directly into the arteries.
• IAA - Insulin autoantibody: antibodies targeting insulin in autoimmune disorders.
• IABP - Intra-aortic balloon pump: a mechanical device that increases myocardial oxygen perfusion and indirectly increases cardiac output.
• IAI - Intra-amniotic infection: an infection within the amniotic fluid.
• IBC - Inflammatory breast cancer: a rare and aggressive form of breast cancer.
• IC - Interstitial cystitis: a chronic condition causing bladder pressure, bladder pain, and sometimes pelvic pain.
• ICCU - Intensive coronary care unit: a hospital ward specialized in the care of patients with heart attacks, unstable angina, cardiac dysrhythmia and other serious cardiac conditions.
• ICD - Implantable cardioverter-defibrillator: a device implanted into patients who are at risk of sudden cardiac death due to ventricular fibrillation and ventricular tachycardia.
• ICD-10 - International classification of diseases, tenth revision: a medical classification list by the world health organization (who).
• ICDS - Implantable cardioverter defibrillator system: see icd.
• ICF - Intracellular fluid: fluid located inside the cells of the body.
• ICG - Indocyanine green: a dye used in medical imaging.
• ICH - Intracranial hemorrhage: a hemorrhage, or bleeding, within the skull.
• ICI - Intracavernosal injection: injection of a drug into the base of the penis.
• ICM - Intracellular matrix: the structure within a cell that provides support and regulates cell behavior.
• ICP - Intracranial pressure: the pressure within the skull.
• ICS - Inhaled corticosteroids: steroids used in breathing treatments.
• ICSI - Intracytoplasmic sperm injection: a procedure in which a single sperm is injected directly into an egg.
• ICU - Intensive care unit: a special department of a hospital or health care facility that provides intensive treatment medicine.
• IDA - Iron deficiency anemia: a common type of anemia that occurs when the body does not have enough iron.
• IDC - Invasive ductal carcinoma: the most common type of breast cancer.
• IDDM - Insulin-dependent diabetes mellitus: former term for type 1 diabetes.
• IDL - Intermediate density lipoprotein: a class of lipoproteins.
• IDP - Infectious disease pharmacokinetics: the study of how drugs to treat infectious diseases are absorbed, distributed, metabolized, and excreted.
• IE - Infective endocarditis: an infection of the inner lining of the heart.
• IF - Intrinsic factor: a protein necessary for the absorption of vitamin b12.
• IFG - Impaired fasting glucose: a condition in which fasting blood glucose levels are elevated above what is considered normal levels but are not high enough to be classified as diabetes mellitus.
• IGF - Insulin-like growth factor: a hormone similar in molecular structure to insulin.
• IGT - Impaired glucose tolerance: a pre-diabetic state of hyperglycemia that is associated with insulin resistance.
• IHC - Immunohistochemistry: a process of selectively imaging antigens in cells of a tissue section by exploiting the principle of antibodies binding specifically to antigens in biological tissues.
• IHD - Ischemic heart disease: a disease characterized by reduced blood supply to the heart.
• IHPS - Infantile hypertrophic pyloric stenosis: a condition in infants blocking food from entering the small intestine.
• IHSS - Idiopathic hypertrophic subaortic stenosis: now known as hypertrophic cardiomyopathy (hcm), a condition where the heart muscle becomes thickened without an obvious cause.
• IIEF - International index of erectile function: a scale that assesses erectile function.
• ILD - Interstitial lung disease: a group of lung diseases affecting the interstitium.
• ILI - Influenza-like illness: a medical diagnosis of possible influenza or another illness causing a set of common symptoms.
• IM - Intramuscular: directly into the muscle.
• IMA - Inferior mesenteric artery: a major artery supplying the large intestine.
• IMB - Intermenstrual bleeding: bleeding between menstrual periods.
• IMI - Intramuscular injection: see im.
• IMM - Immunomodulators: agents that modify the immune response.
• IMN - Intramedullary nailing: a surgical procedure to treat fractures of long bones of the body.
• IMRT - Intensity-modulated radiation therapy: an advanced type of radiation therapy used to treat cancer.
• IMT - Intima-media thickness: a measurement of the thickness of the carotid artery's wall.
• IMV - Intermittent mandatory ventilation: a mode of mechanical ventilation.
• INF(-α/-β/-γ) - Interferon (alpha, beta, gamma): proteins made and released by host cells in response to the presence of pathogens.
• INFX - Infliximab: a chimeric monoclonal antibody against tumor necrosis factor alpha (tnf-α) used to treat autoimmune diseases.
• INH - Isoniazid: a medication used to prevent and treat tuberculosis.
• INR - International normalized ratio: a calculation based on the results of a pt test that determines how blood thinning medications are working.
• INT - Intermittent: occurring at irregular intervals; not continuous or steady.
• IO - Intraosseous infusion: the process of injecting directly into the marrow of a bone.
• IODM - Insulin-dependent diabetes mellitus: see iddm.
• IOL - Intraocular lens: an artificial lens implanted in the eye.
• IOP - Intraocular pressure: the fluid pressure inside the eye.
• IP - Intraperitoneal: within the peritoneal cavity.
• IPF - Idiopathic pulmonary fibrosis: a type of chronic scarring lung disease.
• IPG - Implantable pulse generator: a device that sends electrical impulses to the brain to treat neurological disorders.
• IPH - Idiopathic pulmonary hemosiderosis: a lung disease of unknown cause that results in pulmonary hemorrhage.
• IPMN - Intraductal papillary mucinous neoplasm: a growth in the ducts of the pancreas that can become cancerous.
• IPPB - Intermittent positive pressure breathing: a form of therapeutic respiratory ventilation.
• IPPV - Intermittent positive pressure ventilation: a method of mechanical ventilation.
• IPS - Intraperitoneal sepsis: infection in the peritoneal cavity.
• IQ - Intelligence quotient: a score derived from one of several standardized tests designed to assess intelligence.
• IR - Interventional radiology: a medical sub-specialty of radiology which utilizes minimally-invasive image-guided procedures to diagnose and treat diseases.
• IRDS - Infant respiratory distress syndrome: also known as hyaline membrane disease, a syndrome in premature infants caused by developmental insufficiency of surfactant production and structural immaturity in the lungs.
• IRIDA - Iron-resistant iron deficiency anemia: a genetic disorder that results in anemia resistant to oral iron supplementation.
• IRIS - Immune reconstitution inflammatory syndrome: a condition seen in some cases of aids or immunosuppression, in which the immune system begins to recover, but then responds to a previously acquired opportunistic infection with an overwhelming inflammatory response.
• IS - Immune system: the host defense system comprising many biological structures and processes within an organism that protects against disease.
• ISA - Intrinsic sympathomimetic activity: the property of some beta blockers where they slightly activate the receptor while also blocking it.
• ISDN - Isosorbide dinitrate: a medication used for heart failure, esophageal spasms, and to treat and prevent chest pain from not enough blood flow to the heart.
• ISH - Isolated systolic hypertension: high blood pressure with a systolic number (the top number) higher than 140 mmhg, but a normal diastolic number (the bottom number).
• ISMN - Isosorbide mononitrate: a drug used for the prevention of angina pectoris due to coronary artery disease.
• ISQ - Implant stability quotient: a measurement used in dentistry to determine the stability of a dental implant.
• IT - Intrathecal: administration into the spinal canal.
• ITP - Idiopathic thrombocytopenic purpura: an immune disorder that leads to an abnormally low level of platelets.
• ITU - Intensive therapy unit: another term for icu.
• IU - International unit: a unit of measurement for the amount of a substance, based on measured biological activity or effect.
• IUCD - Intrauterine contraceptive device: a device inserted into the uterus to prevent pregnancy.
• IUD - Intrauterine device: a small contraceptive device inserted into the uterus.
• IUFD - Intrauterine fetal death: the clinical term for stillbirth.
• IUGR - Intrauterine growth restriction: a condition where a fetus is unable to achieve its genetically determined potential size.
• IUI - Intrauterine insemination: a fertility treatment that involves placing sperm inside a woman's uterus to facilitate fertilization.
• IUP - Intrauterine pregnancy: a pregnancy located in the uterus.
• IUPC - Intrauterine pressure catheter: a device used to measure the strength of uterine contractions during labor.
• IUS - Intrauterine system: a hormonal contraceptive device used by women.
• IUT - Intrauterine transfusion: a procedure used in the treatment of fetal anemia.
• IV - Intravenous: administration into the veins.
• IV-DSA - Intravenous digital subtraction angiography: a form of angiography which uses digital subtraction to visualize blood vessels.
• IVC - Inferior vena cava: the large vein that carries de-oxygenated blood from the lower half of the body into the heart.
• IVD - Intervertebral disc: a structure between spinal vertebrae.
• IVDU - Intravenous drug user: a person who uses drugs that are injected into the veins.
• IVF - In vitro fertilization: a process of fertilization where an egg is combined with sperm outside the body.
• IVH - Intraventricular hemorrhage: bleeding into the brain's ventricular system.
• IVIG - Intravenous immunoglobulin: a treatment made up of antibodies that can be given intravenously (through a vein).
• IVP - Intravenous pyelogram: an x-ray test that provides pictures of the kidneys, the bladder, the ureters, and the urethra.
• IVPB - Intravenous piggyback: a method of administering medication intravenously.
• IVPG - Intravenous pyelography: see ivp.
• IVSS - Intravenous steroid saline: a treatment involving a combination of steroids and saline delivered intravenously.
• IVU - Intravenous urography: an x-ray examination of the kidneys, ureters and urinary bladder that uses iodinated contrast material injected into veins.
• IVUS - Intravascular ultrasound: a medical imaging methodology using a specially designed catheter with a mini-ultrasound probe attached to the distal end of the catheter.
• Ig - Immunoglobulin: a group of proteins that function as antibodies.
• IgA - Immunoglobulin a: an antibody that plays a critical role in mucosal immunity.
• IgAV - Immunoglobulin a vasculitis: a disease that results in purpura, arthritis, and abdominal pain.
• IgD - Immunoglobulin d: an antibody isotype that makes up about 1% of proteins in the plasma.
• IgE - Immunoglobulin e: an antibody associated with allergic reactions.
• IgG - Immunoglobulin g: the most common type of antibody found in blood circulation.
• IgG4-RD - Immunoglobulin g4-related disease: a chronic inflammatory condition characterized by tissue infiltration with lymphocytes and igg4-secreting plasma cells.
• IgG4-RKD - Immunoglobulin g4-related kidney disease: kidney disease related to igg4-rd.
• IgG4-ROD - Immunoglobulin g4-related ophthalmic disease: ophthalmic diseases related to igg4-rd.
• IgG4-TIN - Immunoglobulin g4-related tubulointerstitial nephritis: tubulointerstitial nephritis related to igg4-rd.
• IgM - Immunoglobulin m: the first antibody to be made by the body to fight a new infection.
• Inc - Incubation: the process to develop an infection from exposure to the time of the first symptom.
• Inj - Injection: the act of administering a liquid, especially a drug, into the body using a needle and syringe.
• Int - Intubation: the placement of a tube into an external or internal orifice of the body.
• Ix - Investigation: medical procedures performed to diagnose or monitor a disease.