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Idarucizumab is a humanised antibody fragment that rapidly neutralises dabigatran’s anticoagulant effect. It is used in hospital when an adult taking dabigatran has life-threatening or uncontrolled bleeding, or needs emergency surgery or an urgent procedure.
Idebenone is an antioxidant that supports mitochondrial energy production. It is licensed for visual impairment caused by Leber’s hereditary optic neuropathy (LHON) in adolescents and adults, under specialist supervision.
Idelalisib blocks PI3K-delta, a signalling enzyme important to malignant B cells. It has specialist roles in selected chronic lymphocytic leukaemia and treatment-resistant follicular lymphoma in adults.
Idursulfase is an enzyme replacement therapy for Hunter syndrome (mucopolysaccharidosis II). It replaces deficient iduronate-2-sulfatase, helping cells break down glycosaminoglycans that would otherwise accumulate in tissues.
Ifosfamide is a cytotoxic chemotherapy activated in the liver that damages cancer-cell DNA. Specialist oncology teams use it for malignant disease, alone or with other anticancer treatments, radiotherapy or surgery.
Iloprost trometamol provides iloprost, a synthetic version of prostacyclin that widens blood vessels and reduces platelet clumping. Selected UK products are used for primary pulmonary hypertension or severe circulation disorders affecting the limbs.
Imatinib mesilate is a targeted anticancer treatment called a tyrosine kinase inhibitor. It treats selected blood cancers and solid tumours driven by proteins such as BCR-ABL, KIT or PDGFR.
Imipramine hydrochloride is a tricyclic antidepressant. The selected UK oral solution is licensed for depressive illness and night-time bed-wetting in children.
Imiquimod is a topical immune-response modifier used in adults for external genital or perianal warts, selected superficial basal cell carcinomas and certain actinic keratoses.
Imlifidase is an immunosuppressive enzyme used before kidney transplantation. It temporarily breaks down IgG antibodies that would react against an available deceased-donor kidney, allowing some highly sensitised adults to proceed to transplantation.
Human rabies immunoglobulin is a plasma-derived preparation containing antibodies against rabies virus. It provides immediate, short-term protection after a clinically significant exposure while rabies vaccine produces a longer-lasting immune response.
Inclisiran sodium is a small interfering RNA treatment that lowers LDL cholesterol by reducing PCSK9 production in the liver. It is used alongside diet and usually other cholesterol-lowering treatment when LDL cholesterol remains above the agreed goal.
Indacaterol maleate is an inhaled long-acting beta-2 agonist bronchodilator. It keeps the airways open in adults with chronic obstructive pulmonary disease (COPD), but does not treat sudden breathlessness.
Indapamide is a thiazide-like diuretic used to lower high blood pressure. It reduces sodium reabsorption in the kidneys and resistance in small arteries.
This combines perindopril, an ACE inhibitor, with indapamide, a thiazide-like diuretic. The selected product is licensed for adults with essential hypertension not adequately controlled by perindopril alone.
Indapamide hemihydrate is a thiazide-like diuretic that lowers blood pressure. Selected UK products are licensed for essential hypertension in adults.
Indigo carmine is a blue diagnostic dye given into a vein during surgery. It colours urine so the surgical team can see urine flowing through the ureters and identify suspected injury during abdominal or pelvic operations.
Indometacin is a prescription non-steroidal anti-inflammatory drug (NSAID) that reduces pain, inflammation and swelling. The selected UK product is a rectal suppository licensed for several inflammatory and painful conditions.
Indoramin hydrochloride is an alpha-blocker that relaxes smooth muscle around the prostate and urinary outlet, helping urine flow in benign prostatic hyperplasia.
Infliximab is a biological treatment that blocks tumour necrosis factor alpha (TNF-alpha), a protein involved in inflammation. Specialists use it for selected inflammatory bowel, joint, spinal and skin conditions, usually when other treatments have not worked adequately or are unsuitable.
Fluenz is a live, weakened influenza vaccine given as a nasal spray. It helps prevent influenza in eligible children and adolescents but does not protect against every circulating strain.
An injected, non-live vaccine containing inactivated surface antigens from selected influenza strains. It helps prevent influenza in adults and children from 6 months, but protection is not complete and may be weaker with immunosuppression.
Ingenol mebutate was a topical gel for certain sun-damaged actinic keratoses in adults. Its UK licence was suspended and stock recalled in 2020 after a review concluded that its potential skin-cancer risk outweighed its benefits.
A prescription antiviral with immunomodulatory effects, licensed in the UK for mucocutaneous herpes simplex, adjunctive treatment of genital warts and subacute sclerosing panencephalitis.
Inotuzumab ozogamicin is an antibody–drug conjugate licensed in the UK for adults with certain CD22-positive B-cell acute lymphoblastic leukaemias that have returned or not responded to previous treatment.
Insulin aspart is a laboratory-made insulin analogue used to lower blood glucose in diabetes. Rapid-acting forms cover mealtime insulin needs and may be used in suitable pumps, while NovoMix 30 combines rapid and intermediate action.
Insulin degludec is a long-acting insulin analogue that provides background insulin coverage and lowers blood glucose. It treats diabetes in adults and children aged 1 year and over.
This fixed-ratio injection combines basal insulin degludec with the GLP-1 receptor agonist liraglutide. It is used with oral diabetes treatments, diet and exercise to improve glucose control in adults with insufficiently controlled type 2 diabetes.
Insulin detemir is a long-acting insulin analogue that lowers blood glucose in diabetes by providing background, or basal, insulin.
Insulin glargine is a long-acting insulin analogue that lowers blood glucose and provides background insulin for people with diabetes.
Insulin glulisine is a rapid-acting insulin analogue used when insulin is needed to treat diabetes. It mainly controls meal-related rises in blood glucose and can be delivered through a suitable insulin pump.
Insulin lispro is a laboratory-made insulin analogue that lowers blood glucose. Products include fast mealtime solutions and a premixed suspension combining rapid and longer activity.
Interferon beta-1a modifies immune activity. It is a disease-modifying treatment for relapsing multiple sclerosis and selected high-risk adults after a first inflammatory demyelinating event. It does not cure multiple sclerosis.
Interferon beta-1b is an immunomodulating treatment for certain active forms of multiple sclerosis (MS). It is injected under the skin and aims to reduce inflammatory disease activity rather than relieve an established symptom immediately.
Interferon gamma-1b is a recombinant immune-signalling protein used under specialist supervision to reduce serious infections in chronic granulomatous disease and severe, malignant osteopetrosis. It does not replace other infection prevention or treatment.
Iobenguane is a diagnostic radiopharmaceutical containing iodine-123. It is used in specialist imaging to locate certain tumours and assess adrenal or cardiac sympathetic tissue.
Different formulations have different purposes. The topical tincture is an antiseptic for minor cuts and abrasions; the aqueous oral solution is used under specialist supervision before surgery for hyperthyroidism.
Iodixanol is a non-ionic, iodine-containing contrast agent that makes certain structures clearer during X-ray-based diagnostic imaging.
Ioflupane is a radioactive diagnostic tracer used with SPECT brain imaging. It helps specialists assess dopamine-producing nerve terminals when certain movement disorders or causes of dementia are difficult to distinguish; it does not treat these conditions.
Iohexol is a non-ionic, iodine-containing X-ray contrast agent used for diagnostic procedures. It makes blood vessels, organs and body cavities easier to see during scans and specialised X-ray examinations.
Iomeprol is a non-ionic, iodine-containing X-ray contrast agent injected by trained staff to make blood vessels, organs and other structures clearer during CT scans, including CT angiography.
Iopamidol is a non-ionic, iodine-containing contrast agent that makes the digestive tract more visible on X-rays and CT images. This diagnostic liquid is given by mouth or rectally under healthcare supervision; it must not be injected.
Ipilimumab is a monoclonal-antibody immunotherapy that helps T cells attack cancer by blocking the CTLA-4 immune checkpoint. It is used in specialist cancer care, alone or in combination therapy, for several advanced cancers.
Ipratropium bromide is an inhaled anticholinergic bronchodilator that relaxes narrowed airways. The selected nebuliser products are used for reversible bronchospasm in COPD and, with an inhaled beta2 agonist, in asthma.
This inhaled combination contains two bronchodilators that open narrowed airways in different ways. The selected UK product is a nebuliser solution licensed for bronchospasm in chronic obstructive pulmonary disease (COPD) when regular treatment with both components is required.
This nasal spray combines a decongestant with an anticholinergic. It relieves both nasal blockage and a runny nose associated with a common cold in adults.
Ipratropium bromide monohydrate is an inhaled antimuscarinic bronchodilator that relaxes narrowed airways. The selected UK inhaler is licensed for regular treatment of reversible bronchospasm associated with chronic asthma or chronic obstructive pulmonary disease (COPD).
Iptacopan is an oral complement inhibitor that blocks Factor B. It is licensed for adults with paroxysmal nocturnal haemoglobinuria (PNH) with haemolytic anaemia and for adults with complement 3 glomerulopathy (C3G) in specified circumstances.
Irbesartan is a prescription angiotensin receptor blocker that lowers blood pressure. It is licensed for essential hypertension and kidney disease in adults with hypertension and type 2 diabetes.
Irbesartan is a prescription-only angiotensin II receptor blocker (ARB) that relaxes blood vessels and lowers blood pressure. It is also licensed for kidney disease in adults with hypertension and type 2 diabetes.
A cytotoxic chemotherapy that blocks an enzyme cancer cells need to copy DNA. The selected UK product is licensed for advanced colorectal cancer, alone after previous treatment or in specified combinations.
Irinotecan sucrosofate is a liposome-encapsulated form of the chemotherapy irinotecan. In the UK, it is used with other anticancer treatments for adults with metastatic pancreatic adenocarcinoma.
Iron dextran is an iron-carbohydrate complex given by injection or infusion. It treats laboratory-confirmed iron deficiency in adults when oral iron cannot be used, has not worked or iron stores need rapid replenishment.
Iron sucrose is an intravenous iron preparation that supplies iron for haemoglobin production and replenishes body stores. It is used for confirmed iron deficiency when iron is needed rapidly or oral iron is unsuitable or ineffective.
Isatuximab is a targeted monoclonal antibody used with other treatments for multiple myeloma in adults. It attaches to CD38 on myeloma cells, helping the immune system recognise and destroy them.
Isavuconazonium sulfate is a prodrug rapidly converted into the active antifungal isavuconazole. It is a specialist systemic triazole for serious invasive mould infections.
Isocarboxazid is a non-selective monoamine oxidase inhibitor (MAOI) antidepressant licensed for symptoms of depressive illness. Careful management of food and medicine interactions is essential.
Isoflurane is a volatile general anaesthetic breathed into the lungs to induce and maintain unconsciousness during operations. Trained anaesthesia professionals administer it using specialised equipment.
Isoniazid is an antibacterial used against the bacteria that cause tuberculosis (TB). Treatment is managed by a specialist TB team.
This tablet combines three antibiotics that kill tuberculosis bacteria in different environments. It is licensed in the UK for pulmonary tuberculosis under specialist supervision during the initial intensive treatment phase.