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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.
Oritavancin diphosphate is an intravenous antibiotic active against susceptible Gram-positive bacteria. It is used for acute bacterial infections of the skin and underlying tissues and is generally selected with specialist antimicrobial input.
Orlistat is a locally acting gastrointestinal lipase inhibitor used to support weight loss in adults with obesity, or overweight adults with associated risk factors. It is used alongside a nutritionally balanced, reduced-calorie diet and physical activity.
Orphenadrine hydrochloride is an antimuscarinic treatment used to relieve symptoms of parkinsonism, such as stiffness, tremor and slowed movement. The selected UK product is also licensed for parkinsonism caused by medicines, including neuroleptics.
Oseltamivir is a prescription-only oral antiviral active against influenza A and B. It is used in selected circumstances to treat influenza or prevent it after exposure; it does not replace influenza vaccination.
Oseltamivir phosphate is a prescription antiviral used to treat influenza and, in selected circumstances, prevent influenza after exposure.
Osimertinib is a targeted tyrosine kinase inhibitor for adults with non-small-cell lung cancer containing particular EGFR mutations. It may be used after tumour removal, after chemoradiotherapy, or for advanced disease, alone or with specified chemotherapy.
Ospemifene is a non-hormonal selective oestrogen receptor modulator (SERM). It is used after menopause to treat moderate to severe vulval and vaginal atrophy, including dryness, irritation and pain during sex.
Oxaliplatin is a platinum-based cytotoxic chemotherapy, usually combined with fluorouracil and folinic acid for colorectal cancer.
Oxazepam is a benzodiazepine that reduces activity in the brain and can cause sedation. The selected product is licensed for short-term relief of anxiety that is disabling or causes unacceptable distress, including anxiety associated with insomnia or other illness.
Oxcarbazepine is an anti-seizure medicine used to control focal seizures, including those that become bilateral tonic-clonic seizures. Selected UK products are licensed for use alone or alongside another anti-seizure medicine in adults and children aged 6 years and over.
Oxerutins is a systemic vasoprotective bioflavonoid that acts on small blood vessels. It is used to relieve leg and ankle swelling associated with chronic venous insufficiency.
Oxybuprocaine hydrochloride is a local anaesthetic eye drop that temporarily numbs the eye surface. An eye-care professional uses it during examinations and minor procedures.
Oxybutynin hydrochloride is an antimuscarinic that relaxes the bladder muscle. It is mainly used to reduce urinary urgency, frequency and urge incontinence; selected products also cover certain childhood bladder disorders and specialist intravesical treatment of neurogenic detrusor overactivity.
Oxycodone hydrochloride is a strong opioid painkiller used when pain requires opioid treatment. Some UK product licences also cover moderate to severe cancer-related or post-operative pain.
Oxytocin is a synthetic version of a natural hormone that makes the womb contract. In hospital, it is mainly used to start or strengthen labour and to prevent or treat heavy bleeding after birth.
Ozanimod hydrochloride is an immunomodulator that limits movement of certain lymphocytes from lymphoid tissue into the circulation. It is licensed for selected adults with active relapsing-remitting multiple sclerosis or moderately to severely active ulcerative colitis.
Paclitaxel is a taxane chemotherapy that interferes with cancer-cell division. Depending on the formulation, it is used alone or with other anticancer treatments for certain breast, ovarian, lung, pancreatic and AIDS-related Kaposi’s sarcoma indications.
Paclitaxel albumin is a taxane chemotherapy in which paclitaxel is carried in tiny albumin-bound particles. In adults, it is licensed for particular settings of metastatic breast cancer, metastatic pancreatic adenocarcinoma and non-small cell lung cancer.
Palbociclib is a targeted anticancer treatment that blocks proteins involved in cell division. It is usually combined with hormonal treatment for hormone receptor-positive, HER2-negative breast cancer that is locally advanced or metastatic.
Paliperidone is a second-generation antipsychotic and the main active metabolite of risperidone. It is used for schizophrenia; prolonged-release tablets also have a role in schizoaffective disorder, and a long-acting injection is available for maintenance treatment in suitable adults.
A long-acting antipsychotic injection converted in the body to paliperidone. It is used to maintain symptom control in adults with schizophrenia who have responded to paliperidone or risperidone.
Palivizumab is a humanised monoclonal antibody that provides temporary passive protection against respiratory syncytial virus (RSV). It is licensed to prevent serious RSV lower respiratory tract disease requiring hospitalisation in certain high-risk young children. Longer-acting antibodies now usually serve the UK high-risk infant programme.
Palonosetron hydrochloride is an anti-sickness treatment that blocks serotonin signals involved in nausea and vomiting. The selected injection helps prevent sickness caused by certain cancer chemotherapy in adults and children aged at least one month.
Palopegteriparatide is a long-acting parathyroid hormone replacement for adults with chronic hypoparathyroidism. It releases active parathyroid hormone to help regulate calcium and phosphate.
Pamidronate disodium is an intravenous bisphosphonate that slows excessive bone breakdown. It is used for high blood calcium caused by tumours, selected cancer-related bone complications and Paget’s disease of bone.
Pancreatin is a porcine-derived mixture of lipase, amylase and protease. It replaces digestive enzymes when the pancreas does not make or deliver enough, helping digest and absorb fat, starch and protein.
Panitumumab is a targeted monoclonal antibody for adults with wild-type RAS metastatic colorectal cancer. It may be used alone or with specified chemotherapy, depending on previous treatment.
Panobinostat is an oral anticancer histone deacetylase inhibitor. It is licensed with bortezomib and dexamethasone for adults with previously treated relapsed or refractory multiple myeloma.
Pantoprazole sodium sesquihydrate is a proton pump inhibitor that reduces stomach acid. It is used for acid-related disorders, including reflux oesophagitis and peptic ulcers.
Para-aminosalicylic acid is an antimycobacterial treatment used by specialist tuberculosis teams. It is used with other treatments for multidrug-resistant tuberculosis when an effective combination cannot otherwise be formed because of resistance or poor tolerability.
Paracetamol is a painkiller and fever-reducing medicine for adults and children. It treats mild to moderate pain and high temperature but not the underlying cause.
Combines paracetamol for pain and fever with phenylephrine, an oral decongestant. Selected UK products provide short-term relief of cold and flu symptoms, including aches, headache, sore throat, fever and nasal congestion.
Combines paracetamol for pain and fever with pseudoephedrine, an oral decongestant. Selected products are licensed for temporary relief of nasal or sinus congestion with symptoms such as headache, aches, pain or fever.
Combines two pain-relieving substances that work differently. The selected UK product is licensed for moderate to severe pain when both components are considered necessary.
Parathyroid hormone is a laboratory-made copy of the natural hormone that regulates calcium and phosphate. Natpar was used alongside calcium and vitamin D for selected adults with chronic hypoparathyroidism that standard treatment could not adequately control. Its UK marketing authorisation was withdrawn on 1 July 2026.
Parecoxib sodium is an injectable non-steroidal anti-inflammatory drug (NSAID) converted in the body to the selective COX-2 inhibitor valdecoxib. It is used in adults for short-term relief of pain after an operation.
Paricalcitol is a synthetic active vitamin D analogue used to control excess parathyroid hormone in chronic kidney disease. It helps manage associated mineral and bone disorder.
Paroxetine is a prescription antidepressant in the selective serotonin reuptake inhibitor (SSRI) class. It is used for depression and several anxiety-related conditions, including obsessive-compulsive disorder, panic disorder and post-traumatic stress disorder.
Paroxetine hydrochloride anhydrous is the active ingredient in an SSRI antidepressant. It is licensed for depression and several anxiety-related conditions in adults.
Paroxetine hydrochloride hemihydrate provides paroxetine, a prescription selective serotonin reuptake inhibitor (SSRI) antidepressant. It is licensed for depression and several anxiety-related conditions.
Pasireotide diaspartate is an injectable somatostatin analogue that reduces excess pituitary hormone release. It is used for adults with Cushing’s disease when surgery is unsuitable or has not worked.
Pasireotide pamoate is a long-acting somatostatin analogue given by deep injection into a buttock muscle. It is used in adults with Cushing’s disease or acromegaly in defined situations where surgery is unsuitable or unsuccessful; acromegaly must also be inadequately controlled by another somatostatin analogue.
Patiromer sorbitex calcium is a non-absorbed potassium binder used to treat high blood potassium. It removes potassium through the bowel and is intended for ongoing control rather than emergency correction.