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Prasterone is a steroid precursor that vaginal cells convert into small amounts of oestrogens and androgens. It is used locally for moderate to severe vulval and vaginal atrophy after the menopause.
Prasugrel is an antiplatelet treatment that reduces platelets sticking together and forming harmful clots. It is usually used with aspirin after an acute coronary syndrome in adults undergoing coronary intervention.
Prasugrel besilate is an antiplatelet treatment that makes platelets less able to form harmful clots. It is usually used with aspirin in adults with acute coronary syndrome who undergo a procedure to open a coronary artery.
Prasugrel hydrochloride is an antiplatelet treatment that reduces platelet clumping and blood-clot formation. In the UK, it is licensed with aspirin for adults with acute coronary syndrome who undergo coronary intervention such as angioplasty or stent placement.
Pravastatin sodium is a statin that reduces cholesterol production in the liver and helps clear LDL cholesterol from the blood. It is used alongside measures such as diet to treat certain lipid disorders and reduce cardiovascular risk.
Prazosin hydrochloride is a prescription alpha-1 blocker that relaxes blood vessels and smooth muscle. In the UK, it is licensed for hypertension, certain cases of heart failure, Raynaud’s symptoms and urinary obstruction caused by benign prostate enlargement.
Prednisolone acetate is a corticosteroid eye-drop suspension used to reduce inflammation in adults when infection has been excluded.
Prednisone is a systemic corticosteroid that reduces inflammation and suppresses immune activity. The selected UK product contains prednisolone, the active corticosteroid used for inflammatory, allergic, autoimmune and some malignant conditions.
Pregabalin is a prescription gabapentinoid. Standard-release products are licensed in adults for neuropathic pain, add-on treatment for partial seizures and generalised anxiety disorder. Prolonged-release Misabri PR is licensed only for neuropathic pain.
Prilocaine hydrochloride is an amide local anaesthetic that temporarily blocks nerve signals. The selected UK product is used in adults to produce spinal anaesthesia for short surgical procedures.
Primidone is an antiseizure treatment related to barbiturates. It is licensed for several forms of epilepsy and essential tremor, and is partly converted to the active metabolites phenobarbital and PEMA.
Procarbazine hydrochloride is an oral cytotoxic chemotherapy that interferes with cancer-cell growth. It is usually used with other anticancer treatments, particularly for Hodgkin lymphoma, and is also licensed for certain advanced lymphomas and resistant solid tumours.
Prochlorperazine maleate is a phenothiazine anti-sickness treatment that blocks dopamine signalling. Selected buccal products are licensed for nausea and vomiting with migraine previously diagnosed by a doctor.
Prochlorperazine mesilate is a phenothiazine that blocks dopamine activity in the brain. It is commonly used as an anti-sickness treatment; the selected injection is also licensed for schizophrenia and acute mania.
Procyclidine hydrochloride is an antimuscarinic that reduces parkinsonian movement symptoms. Selected oral products are licensed for Parkinson’s disease and troublesome movement effects caused by neuroleptic medicines.
Progesterone is a natural progestogen hormone that changes and supports the womb lining. UK products are used with oestrogen in HRT, for fertility treatment and, in selected high-risk pregnancies, to help prevent preterm birth.
Promazine hydrochloride is a sedating phenothiazine antipsychotic. The selected UK product is used alongside non-medicine measures for short-term management of moderate to severe agitation and restlessness when there is a risk of harm.
Propafenone hydrochloride is a class Ic anti-arrhythmic that changes electrical conduction through the heart. It is used under specialist supervision to treat or prevent certain ventricular and intermittent supraventricular abnormal rhythms, particularly when standard therapy is unsuitable or has failed.
Propamidine isetionate is a topical aromatic diamidine with disinfectant and antifungal activity. The selected UK product is used for minor infections of the eye or eyelid, including conjunctivitis and blepharitis.
Propantheline bromide is an antimuscarinic that reduces involuntary smooth-muscle activity and secretions. It is licensed for adults with gastrointestinal disorders involving smooth-muscle spasm, excessive sweating or enuresis.
Propofol is a short-acting intravenous general anaesthetic. Trained clinicians use it to start or maintain general anaesthesia, provide procedural sedation, or sedate ventilated adults in intensive care.
Propylthiouracil is an antithyroid treatment that reduces thyroid hormone production. It is used to control an overactive thyroid, with blood tests guiding treatment and safety checks.
Protamine sulfate is an antidote that counteracts the blood-thinning effect of heparin. It is given intravenously by healthcare professionals when heparin needs to be neutralised, including around surgery, dialysis or excessive bleeding.
Protein C concentrate is a plasma-derived replacement for a natural blood protein that limits excessive clotting. It is mainly used for serious clotting complications in people with severe congenital protein C deficiency.
Proxymetacaine hydrochloride is a local anaesthetic eye drop that temporarily numbs the eye’s surface. An eye-care professional usually applies it before examinations, pressure measurement or minor eye procedures.
Prucalopride is a gastrointestinal prokinetic that stimulates bowel movement. It is licensed for symptomatic treatment of chronic constipation in adults when laxatives have not provided adequate relief.
Pseudoephedrine hydrochloride is an oral sympathomimetic decongestant. It temporarily reduces swelling inside the nose and sinuses, helping air and mucus move more freely when congestion accompanies conditions such as a cold.
This combines pseudoephedrine, a nasal decongestant, with triprolidine, a sedating antihistamine. It provides short-term symptom relief when congestion occurs alongside sneezing, a runny nose or watery eyes.
Pyrazinamide is an antibiotic used with other antituberculosis antibiotics to treat active tuberculosis caused by Mycobacterium tuberculosis. Resistance develops rapidly if it is used alone.
Pyridostigmine bromide is a reversible cholinesterase inhibitor that improves communication between nerves and muscles. It is mainly used to relieve muscle weakness in myasthenia gravis and is also licensed for paralytic ileus and difficulty passing urine after surgery.
Pyridoxine is a form of vitamin B6 that the body converts into active coenzymes. Prescription tablets are mainly used for vitamin B6 deficiency, certain cases of sideroblastic anaemia, and nerve damage caused by isoniazid.
Pyridoxine hydrochloride is a prescription form of vitamin B6. It replaces deficiency and supports vitamin B6-dependent processes involved in metabolism, haemoglobin formation and nerve function.
Pyrimethamine is an antiprotozoal that disrupts folate metabolism in parasites. Its licensed role is combination treatment of toxoplasmosis, particularly infection affecting the eyes, an unborn baby or people with impaired immunity. Mild or symptom-free infection does not usually require treatment.
Quinagolide hydrochloride is a non-ergot dopamine D2-receptor agonist that reduces prolactin release from the pituitary gland. It is used for hyperprolactinaemia that is idiopathic or caused by a prolactin-secreting pituitary adenoma.
Quinine bisulfate is a prescription antimalarial alkaloid. The selected product is licensed for falciparum malaria and for selected adults with night-time leg cramps that regularly disrupt sleep; it is not a routine treatment for leg cramps.
Quinine sulfate is a prescription-only cinchona alkaloid used for falciparum malaria. It may also be considered for nocturnal leg cramps that regularly disrupt sleep, but is not a routine cramp treatment because benefit is modest and serious adverse effects can occur.
Quizartinib dihydrochloride is an oral protein kinase inhibitor used for adults with newly diagnosed acute myeloid leukaemia whose cancer has the FLT3-ITD alteration. It is used with chemotherapy and may then continue as maintenance treatment.
Rabbit anti-human thymocyte immunoglobulin is a biological immunosuppressant containing rabbit-derived antibodies that reduce immune-cell activity. It is licensed to prevent rejection after kidney or heart transplantation and to treat kidney-transplant rejection that has not responded to corticosteroids. It is normally combined with other immunosuppressants.
Rabeprazole sodium is a proton pump inhibitor that reduces acid production in the stomach. It is used for acid reflux disease, peptic ulcers and uncommon conditions involving excessive acid secretion; it can also accompany antibiotics when treating Helicobacter pylori infection associated with an ulcer.
Rabies vaccine is an inactivated vaccine that helps the immune system make antibodies against rabies virus. It is used before exposure in people at increased risk and after a possible exposure to help prevent rabies. Possible exposure requires urgent medical assessment even if the person was vaccinated previously.
Radium-223 dichloride is a radioactive treatment that targets areas of prostate cancer in bone. It is used for selected adults with hormone-resistant prostate cancer causing symptoms from bone metastases, without known spread to internal organs.
Raloxifene hydrochloride is a selective oestrogen receptor modulator (SERM) used to prevent and treat osteoporosis after the menopause. It reduces vertebral fractures, but a reduction in hip fractures has not been demonstrated.
Raltegravir is an antiretroviral that blocks HIV integrase. It is used with other active treatments to control HIV-1; it does not cure HIV.
Raltegravir potassium is an antiretroviral that treats HIV-1 by blocking HIV integrase. It is used with other active HIV treatments to reduce viral replication; it does not cure HIV.
Raltitrexed is an antifolate chemotherapy that blocks cancer cells from making DNA. It is licensed for palliative treatment of advanced colorectal cancer when fluorouracil and folinic acid treatment is unsuitable or not tolerated.
Ramipril is a prescription angiotensin-converting enzyme (ACE) inhibitor used for high blood pressure, heart failure, after some heart attacks, specified kidney disease and reducing cardiovascular risk in selected people.
Ramucirumab is a targeted monoclonal antibody that blocks a signal involved in forming tumour blood vessels. It is used for selected advanced stomach, bowel, lung and liver cancers, either alone or with other anticancer treatments.
Ranibizumab is a biological anti-VEGF treatment injected into the eye by an ophthalmology specialist. It is used for retinal conditions in which abnormal blood vessels or fluid leakage threaten vision.
Ranitidine hydrochloride is an H2-receptor antagonist that reduces stomach-acid production. It is not currently available in the UK following precautionary discontinuation over an impurity concern.
Ranolazine is an anti-anginal treatment for adults with stable angina. It is usually added when first-line treatments do not control symptoms adequately or cannot be tolerated; it does not treat an angina attack that is already happening.
Rasagiline hemitartrate is an oral monoamine oxidase-B inhibitor used to treat adults with Parkinson’s disease. It may be used alone or alongside levodopa when symptoms return as levodopa’s effect wears off.
Rasagiline mesilate is a monoamine oxidase-B inhibitor used to manage symptoms of Parkinson’s disease. It may be used alone or alongside levodopa when its effects wear off between treatments.
Rasagiline tartrate is a selective MAO-B inhibitor used in adults with idiopathic Parkinson’s disease. It may be used alone or added to levodopa when symptoms return towards the end of a levodopa dose. It slows dopamine breakdown in the brain, helping to improve movement symptoms.
Rasburicase is a recombinant urate-oxidase enzyme used around the start of chemotherapy. It rapidly breaks down excess uric acid, helping protect the kidneys when blood cancers are likely to undergo rapid tumour lysis.
Ravulizumab is a monoclonal antibody that blocks complement protein C5. It is given by specialist intravenous infusion to control complement-mediated damage in selected blood, kidney, neuromuscular and neuroinflammatory disorders.
Reboxetine is a prescription antidepressant that mainly increases noradrenaline signalling in the brain. In the UK, it is licensed to treat major depression and to maintain improvement in people who initially respond.
This is an inactivated oral vaccine containing killed Vibrio cholerae O1 bacteria and a non-toxic recombinant part of cholera toxin. It is used for selected travellers aged 2 years and over whose destination and travel conditions create a meaningful cholera risk; most travellers do not need it. Vaccination does not replace careful food, water and hygiene precautions.
Regadenoson is a selective coronary vasodilator used for diagnostic cardiac procedures. It temporarily increases coronary blood flow so clinicians can assess heart-muscle perfusion or evaluate a single narrowed coronary artery during angiography.
Regorafenib is an oral targeted cancer treatment that blocks several protein kinases involved in tumour growth and blood-vessel formation. It is licensed for selected adults with previously treated metastatic colorectal cancer, gastrointestinal stromal tumours or hepatocellular carcinoma.
Remdesivir is a direct-acting antiviral used to treat COVID-19. It is given into a vein by a healthcare professional to eligible people who need supplemental oxygen or who are at increased risk of severe illness.