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Neratinib maleate is an oral targeted treatment that blocks HER-family growth signals in cancer cells. In the UK, it is licensed after trastuzumab-based treatment for certain adults with early-stage, hormone receptor-positive, HER2-positive breast cancer.
Netupitant + palonosetron hydrochloride combines two anti-sickness agents that block different vomiting pathways. It is used in adults to prevent both early and delayed nausea and vomiting caused by certain cancer chemotherapy.
Nevirapine is an antiretroviral from the non-nucleoside reverse transcriptase inhibitor class. It helps control HIV-1 and is used with other active antiretrovirals, not by itself.
Nevirapine anhydrate is a non-nucleoside reverse transcriptase inhibitor (NNRTI) used to treat HIV-1. It is prescribed by an HIV specialist alongside other antiretroviral medicines to suppress the virus and limit resistance.
Nevirapine hemihydrate is a non-nucleoside reverse transcriptase inhibitor used with other antiretrovirals to control HIV-1. It does not cure HIV and should not be used alone because resistance can develop quickly.
Nicardipine hydrochloride is a dihydropyridine calcium-channel blocker that relaxes arteries and lowers blood pressure. The selected intravenous product is used in hospital for acute life-threatening hypertension and high blood pressure after an operation.
Nicorandil widens arteries and veins and is used for symptom control in adults with stable angina when first-line treatments are unsuitable or do not control symptoms adequately.
Nicotinamide is a form of vitamin B3 with anti-inflammatory activity. As a topical gel, it is licensed to treat mild to moderate inflammatory acne.
Nicotine replacement therapy supplies nicotine without tobacco smoke to reduce cravings and withdrawal while stopping or reducing smoking or vaping.
Nicotine bitartrate dihydrate is used in lozenges to deliver nicotine through the mouth lining. It is nicotine replacement therapy (NRT) that can reduce cravings and withdrawal symptoms while stopping smoking.
A nicotine replacement chewing gum used to relieve nicotine cravings and withdrawal symptoms when stopping or reducing smoking.
Nicotine resinate is used in oral nicotine replacement products such as medicated gum and lozenges. It supplies nicotine without tobacco smoke to reduce cravings and withdrawal symptoms while stopping or reducing tobacco or electronic-cigarette use.
Nifedipine is a dihydropyridine calcium-channel blocker that relaxes arteries. Selected modified-release products are licensed for high blood pressure and prevention of chronic stable angina.
Nilotinib is a targeted tyrosine kinase inhibitor used to treat Philadelphia chromosome-positive chronic myeloid leukaemia (CML). It blocks the abnormal BCR-ABL protein that drives the growth of leukaemia cells.
Nilotinib is a targeted tyrosine kinase inhibitor for Philadelphia chromosome-positive chronic myeloid leukaemia (CML). It is prescribed and monitored by a specialist cancer team.
Nimodipine is a dihydropyridine calcium-channel blocker with particular effects on blood vessels in the brain. It is used after aneurysmal subarachnoid haemorrhage to prevent or treat ischaemic neurological problems.
Nintedanib is a tyrosine kinase inhibitor that slows processes involved in lung scarring. It is mainly used for progressive fibrosing lung diseases and, separately, with docetaxel for certain previously treated lung cancers.
Niraparib tosylate monohydrate is a targeted anticancer treatment called a PARP inhibitor. It is used as maintenance treatment for certain ovarian, fallopian tube or primary peritoneal cancers that have responded to platinum-based chemotherapy.
Nirmatrelvir + ritonavir is an oral antiviral combination used to treat COVID-19. It is licensed for adults who do not need supplemental oxygen and are at increased risk of developing severe illness.
Nitisinone is an oral treatment that blocks part of the pathway used to break down tyrosine. Selected products are licensed for hereditary tyrosinaemia type 1 alongside dietary restriction, and for alkaptonuria in adults.
Nivolumab is a monoclonal antibody that helps immune T cells recognise and attack cancer cells. It is used alone or with other anticancer treatments for several solid tumours and classical Hodgkin lymphoma, including treatment around surgery and for advanced disease.
Nivolumab + relatlimab is a fixed combination of two monoclonal-antibody immunotherapies. It is used as first-line treatment for advanced melanoma that cannot be removed surgically or has spread, in adults and adolescents aged 12 years and older.
Nizatidine is an H2-receptor antagonist that reduces stomach-acid production. It is used for gastro-oesophageal reflux disease and several types of stomach or duodenal ulcer.
This category includes unrelated products without a conventional active ingredient: a skin emollient, an eye lubricant and a preserved injection diluent. They are not interchangeable.
Nonacog alfa is a recombinant form of clotting factor IX. It replaces the factor IX lacking in haemophilia B to help prevent or control bleeding and may be used in all age groups.
Nonacog beta pegol is a recombinant clotting factor IX replacement modified with polyethylene glycol so that it remains in the circulation longer. It is used to prevent and treat bleeding in people of any age with haemophilia B.
Nonacog gamma is a recombinant form of human clotting factor IX. It replaces deficient factor IX in people with haemophilia B, helping to treat bleeding and prevent future bleeds.
Nonoxinol-9 is a non-hormonal spermicide used with a diaphragm or cervical cap, not alone. The selected UK product, Gygel Contraceptive Jelly, is discontinued.
Noradrenaline, also called norepinephrine, is a vasopressor that narrows blood vessels and raises blood pressure. It is given in hospital as an emergency treatment for adults with acute hypotension.
Noradrenaline tartrate is a vasopressor that narrows blood vessels and raises blood pressure. It is given intravenously by trained healthcare professionals for severe low blood pressure or peri-operative hypotension.
Norethisterone is a synthetic progestogen related to progesterone. It is used for menstrual bleeding disorders, endometriosis, premenstrual symptoms and postponing menstruation; Utovlan also has a specialist breast-cancer indication.
Norethisterone enantate is a long-acting progestogen contraceptive given by injection. In the UK, the selected product is licensed for short-term contraception, particularly while a partner’s vasectomy becomes effective or after rubella immunisation while pregnancy should be avoided.
Nortriptyline hydrochloride is a tricyclic antidepressant. Selected UK products are licensed for major depressive episodes; it is also commonly prescribed outside its licence for nerve pain.
Nusinersen sodium is an antisense oligonucleotide used to treat 5q spinal muscular atrophy. It changes processing of SMN2 genetic instructions so that more functional survival motor neuron protein is produced.
Nystatin is an antifungal used mainly against Candida yeasts. The oral suspension acts locally in the mouth and digestive tract because very little is absorbed into the bloodstream.
Obeticholic acid is a prescription farnesoid X receptor (FXR) agonist used for adults with primary biliary cholangitis. It may be used with ursodeoxycholic acid when the response is inadequate, or alone when ursodeoxycholic acid cannot be tolerated.
Obinutuzumab is a monoclonal antibody that targets CD20 on B lymphocytes. In the UK, it is used for certain adults with chronic lymphocytic leukaemia, follicular lymphoma or active lupus nephritis, usually alongside other treatments.
Ocrelizumab is a monoclonal antibody for adults with active relapsing forms of multiple sclerosis and selected early primary progressive multiple sclerosis. It targets certain B cells to reduce inflammatory disease activity but does not cure MS.
Octocog alfa is a recombinant form of clotting factor VIII. It temporarily replaces the factor VIII missing in haemophilia A, helping treat bleeding and prevent future bleeds.
Octreotide is a synthetic version of somatostatin, a hormone that limits release of growth hormone and several digestive-system hormones. This prolonged-release product is used to maintain control of acromegaly in adults who have already responded to and tolerated a somatostatin analogue.
Octreotide acetate is a synthetic version of somatostatin. It suppresses selected hormones and digestive secretions to help control acromegaly, hormone-related tumour symptoms and certain pituitary or neuroendocrine tumours.
Odevixibat sesquihydrate is an ileal bile acid transporter inhibitor that acts mainly within the intestine. It is used under specialist supervision for progressive familial intrahepatic cholestasis and cholestatic itching associated with Alagille syndrome in patients aged 6 months or older.
Conjugated oestrogens are a mixture of oestrogen hormones used as systemic hormone replacement therapy. They replace declining oestrogen after menopause, helping relieve deficiency symptoms and, in selected postmenopausal women, prevent osteoporosis.
Ofatumumab is a monoclonal antibody that targets CD20-positive B cells involved in multiple sclerosis inflammation. It is a specialist disease-modifying treatment for adults with active relapsing forms of multiple sclerosis and aims to reduce future disease activity rather than relieve symptoms immediately.
Ofloxacin is a fluoroquinolone antibiotic available as tablets and eye drops. Tablets treat selected susceptible bacterial infections when other commonly recommended antibiotics are inappropriate; eye drops treat susceptible external eye infections.
Olanzapine is an antipsychotic used mainly for schizophrenia and manic episodes associated with bipolar disorder. It can also help prevent further bipolar episodes after mania has responded to treatment.
Olanzapine pamoate monohydrate is a long-acting injectable antipsychotic used to maintain treatment in adults with schizophrenia who have responded to and tolerated oral olanzapine.
Olipudase alfa is a replacement form of acid sphingomyelinase, an enzyme that is deficient in acid sphingomyelinase deficiency (ASMD). It is used in adults and children with type A/B or type B disease to treat manifestations outside the central nervous system.
This is a sterile fat emulsion given into a vein as part of parenteral nutrition. It supplies energy and essential fatty acids when adequate nutrition cannot be taken or absorbed through the digestive system.
Olmesartan medoxomil is an angiotensin receptor blocker used to lower high blood pressure. It relaxes blood vessels by reducing the effects of angiotensin II.
An inhaled long-acting beta2 agonist that relaxes airway muscle. It is used for maintenance treatment of COPD in adults, not for sudden breathlessness or asthma.
A combination inhaler containing two long-acting bronchodilators, tiotropium and olodaterol. It is used for maintenance treatment to relieve symptoms of chronic obstructive pulmonary disease (COPD) in adults and is not a rescue inhaler for sudden breathlessness.
Olopatadine hydrochloride is an antiallergic eye treatment with antihistamine and mast-cell-stabilising effects. The selected product is licensed for seasonal allergic conjunctivitis in adults, helping relieve itchy, watery, red or inflamed eyes.
Omalizumab is a biological treatment that binds immunoglobulin E (IgE), an antibody involved in allergic inflammation. It is used as an add-on treatment for selected people whose severe allergic asthma, severe nasal polyps or chronic spontaneous urticaria remain inadequately controlled.
Omega-3-acid ethyl esters 90 is a purified mixture containing the omega-3 fatty acids EPA and DHA as ethyl esters. The selected products are used alongside dietary measures to lower certain raised blood triglyceride levels when diet alone has not produced an adequate response.
Onasemnogene abeparvovec is an AAV9-based gene therapy that delivers a functional copy of the SMN1 gene. It is used for specified forms of genetically confirmed 5q spinal muscular atrophy and is administered in a specialist clinical centre.
Ondansetron is an anti-sickness treatment that blocks serotonin signals involved in nausea and vomiting. Oral products are mainly used around cancer treatment and surgery, with licensed uses varying by product and age.
Ondansetron hydrochloride dihydrate is the salt form of ondansetron, an anti-sickness treatment. In selected UK products, it is mainly used to prevent or manage nausea and vomiting associated with cancer treatment or surgery.
Opicapone is a catechol-O-methyltransferase (COMT) inhibitor used alongside levodopa-based treatment for Parkinson’s disease. It helps levodopa remain effective for longer when symptoms return near the end of a levodopa dose.
Opium tincture is an oral extract of raw opium containing morphine and other opium alkaloids. The selected UK product is licensed for symptomatic treatment of severe diarrhoea in adults when other anti-diarrhoea treatments have not worked sufficiently.