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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.
This combination contains two antibiotics that kill tuberculosis bacteria in different ways. The selected UK product is licensed for all forms of tuberculosis and is used under specialist supervision.
A wash-off emollient gel that replaces ordinary soap or cleanser for dry, chapped, itchy or inflamed skin. Its oily ingredients soften skin and reduce moisture loss while washing.
Isosorbide dinitrate widens blood vessels and reduces the heart’s workload. Tablets are mainly used to prevent angina and may be used for heart failure; injectable forms are used in hospital for selected acute cardiac conditions.
Isosorbide mononitrate is a long-acting nitrate that widens blood vessels and reduces the heart’s workload. Selected UK products are licensed to prevent angina; it is not fast enough to treat a sudden attack.
Isotretinoin is an oral retinoid used under specialist supervision for severe acne that has not responded adequately to antibacterial and topical treatments, particularly when permanent scarring is a risk.
Ispaghula husk is a plant-derived, bulk-forming laxative. It absorbs water in the bowel, increasing and softening stool bulk to support easier passage and regularity.
This combination contains ispaghula husk, a bulk-forming fibre, and mebeverine, an antispasmodic. It is licensed for symptomatic relief of irritable bowel syndrome (IBS), particularly altered bowel habit with cramps or spasms.
Itraconazole treats or prevents selected fungal and yeast infections. The oral solution is mainly licensed for candidosis or prevention in certain immunocompromised patients; the intravenous formulation treats specified serious systemic infections.
Ivabradine lowers heart rate by acting on the heart’s natural pacemaker. In selected adults, it is used for stable angina symptoms or alongside standard treatment for chronic heart failure.
Ivabradine hydrochloride selectively slows the heart’s natural pacemaker without directly reducing heart muscle contraction. Selected UK products are licensed for symptom control in chronic stable angina and for certain adults with stable chronic systolic heart failure who remain in sinus rhythm.
Ivacaftor is a CFTR modulator used for cystic fibrosis caused by specific CFTR gene mutations. It may be used alone or as part of an approved combination treatment.
A CFTR modulator combination for cystic fibrosis caused by two copies of the F508del CFTR mutation. It helps more CFTR protein reach the cell surface and work effectively.
Ivacaftor + tezacaftor is a CFTR modulator treatment for cystic fibrosis caused by specific CFTR gene mutations. The combination tablet is used with a separate ivacaftor tablet under specialist care.
Ivermectin is an antiparasitic treatment available as oral tablets and facial cream. UK-licensed uses include selected worm infections, confirmed scabies and inflammatory rosacea lesions in adults.
Ivosidenib is an oral targeted anticancer treatment that inhibits mutated IDH1. It is licensed for selected adults with IDH1 R132-mutated acute myeloid leukaemia or cholangiocarcinoma. An appropriate test must confirm the mutation before treatment.
Ivy leaf dry extract is a herbal preparation made from Hedera helix leaves. The selected UK syrup is traditionally used to relieve chesty coughs associated with the common cold; this is based on long-standing use rather than demonstrated clinical effectiveness.
Ixazomib citrate is an oral proteasome inhibitor used to treat multiple myeloma. In the UK, it is licensed with lenalidomide and dexamethasone for adults who have received at least one previous therapy.
Ixekizumab blocks the inflammatory protein interleukin-17A. UK-licensed uses include certain forms of psoriasis, psoriatic arthritis and axial spondyloarthritis, usually under specialist supervision.
A topical preparation that soothes and protects the skin. It acts locally rather than throughout the body.
An oral suspension combining an adsorbent, antacid and a small amount of opioid. It is licensed to relieve diarrhoea and upset-stomach symptoms in adults and young people over 12.