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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.
Patisiran sodium is a small interfering RNA treatment that reduces production of transthyretin protein in the liver. It is used for adults with hereditary transthyretin-mediated amyloidosis affecting the nerves.
Pazopanib hydrochloride is an oral targeted anticancer treatment called a multikinase inhibitor. It is used in adults with advanced kidney cancer and selected advanced soft-tissue sarcomas.
Pegaspargase is an enzyme-based cancer treatment used for acute lymphoblastic leukaemia (ALL). It is given with other anticancer treatments to adults and children, including babies.
Pegcetacoplan is a complement inhibitor given by infusion under the skin. In the UK, it is used for haemolytic anaemia caused by paroxysmal nocturnal haemoglobinuria (PNH), and for specified complement-mediated kidney diseases.
Pegfilgrastim is a long-acting granulocyte colony-stimulating factor that helps bone marrow produce and release neutrophils. It is used in adults receiving certain cancer chemotherapy to shorten neutropenia and reduce febrile neutropenia.
Peginterferon alfa-2a is a long-acting interferon given by injection. It is licensed for polycythaemia vera, essential thrombocythaemia and selected people with chronic hepatitis B or C.
Peginterferon beta-1a is a long-acting interferon beta treatment for relapsing-remitting multiple sclerosis in adults. It aims to reduce inflammatory disease activity; it does not cure MS or repair existing nerve damage.
Pegunigalsidase alfa is an enzyme replacement therapy for adults with confirmed Fabry disease. It replaces deficient alpha-galactosidase A, helping reduce the build-up of fatty substances within cells.
Pegvisomant is a growth hormone receptor antagonist used to control acromegaly in adults. It is usually considered when surgery or radiotherapy has not controlled the condition and somatostatin analogue treatment has been ineffective or not tolerated.
Pegzilarginase is a modified recombinant human arginase enzyme used to treat arginase 1 deficiency, also called hyperargininaemia. It lowers excess arginine and is used alongside individualised dietary and other disease management.
An oral herbal preparation containing a dry extract of Pelargonium root from one or both named species. It is registered to relieve common-cold symptoms such as cough, sore throat and a blocked or runny nose, based on traditional use rather than demonstrated clinical effectiveness.
Pembrolizumab is a monoclonal antibody and immune checkpoint inhibitor used to treat several cancers. It may be used alone or alongside other cancer treatments, depending on the cancer type, stage and tumour-test results.
Pemetrexed diarginine is an antifolate chemotherapy given into a vein. It is used in adults with certain non-squamous non-small-cell lung cancers and, with cisplatin, unresectable malignant pleural mesothelioma.
Pemetrexed disodium is an antifolate chemotherapy that interferes with processes cancer cells need to make DNA. In the UK, it is licensed for selected non-squamous non-small-cell lung cancers and, with cisplatin, unresectable malignant pleural mesothelioma.
Pemetrexed disodium hemipentahydrate is a cytotoxic antifolate chemotherapy used in adults for unresectable malignant pleural mesothelioma and certain locally advanced or metastatic non-squamous non-small-cell lung cancers, with cisplatin or alone depending on the treatment setting.
Pemetrexed disodium heptahydrate is an intravenous antifolate chemotherapy that disrupts processes cancer cells need to make DNA. It is licensed for selected non-squamous non-small-cell lung cancers and, with cisplatin, unresectable malignant pleural mesothelioma.
Pemetrexed disodium hydrate is a cytotoxic antifolate that disrupts processes cancer cells need to make DNA. It is used for malignant pleural mesothelioma and selected non-small-cell lung cancers, either alone or with cisplatin depending on the clinical setting.