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Ponesimod is a selective immunosuppressant used for adults with active relapsing forms of multiple sclerosis. It reduces the movement of certain immune cells into the brain and spinal cord, helping limit inflammatory nerve damage.
Poractant alfa is a natural lung surfactant prepared from pig lungs. It is given directly into a newborn baby's airway to treat respiratory distress syndrome and may also be used preventively in certain premature babies requiring intubation.
Porcine insulin is purified insulin derived from pigs. It replaces insulin that the body cannot produce adequately, lowering blood glucose and helping prevent ketone formation. The selected biphasic product combines neutral and isophane components for an intermediate-duration effect.
Posaconazole is a triazole antifungal used to treat serious infections caused by susceptible fungi. It is also used to prevent invasive fungal infections in people at high risk because of intensive chemotherapy, stem-cell transplantation or immunosuppression.
Potassium acid phosphate is an electrolyte concentrate that supplies potassium and phosphate. In the selected UK product, it is used in hospital as part of intravenous electrolyte replacement therapy.
This is an oral electrolyte replacement containing two potassium salts. It is used to prevent or treat low blood potassium caused by medicines, fluid losses, reduced intake or certain acid–base disorders.
An alginate reflux suppressant that acts mainly in the stomach to relieve heartburn, acid regurgitation and reflux-related indigestion.
Potassium chloride is a potassium salt used to replace potassium when blood or body stores are too low. The selected oral syrup is licensed for hypokalaemia and potassium deficiency caused by renal or non-renal losses.
A rice-based oral rehydration preparation that replaces water and electrolytes lost during watery diarrhoea and can help stools return towards normal.
A hypertonic electrolyte infusion used to replace potassium when oral replacement is inadequate, particularly in closely monitored critical-care settings where fluid volume may need to be limited. It is given through a central vein using an infusion pump.
Potassium citrate makes urine less acidic and increases urinary citrate. Products are licensed either for cystitis symptom relief or for selected kidney-stone disorders and renal tubular acidosis; it is not an antibiotic.
This combination is a reflux suppressant used for heartburn, acid regurgitation and indigestion caused by stomach contents flowing into the oesophagus. It forms a floating protective raft rather than relying on absorption into the bloodstream.
Potassium iodide is a stable, non-radioactive iodine salt that reduces the thyroid’s uptake of radioactive iodine after a nuclear accident. It protects only the thyroid and should be taken only when public authorities instruct.
Potassium para-aminobenzoate is an oral antifibrotic treatment. In the UK, it is licensed for adults with Peyronie’s disease or scleroderma, although its precise mechanism and individual benefit are uncertain.
Povidone iodine is a broad-spectrum antiseptic that releases iodine to inactivate bacteria, fungi, viruses and spores. This eye preparation is used by healthcare professionals to clean the eye surface and surrounding skin before eye surgery.
Pralsetinib is a targeted protein kinase inhibitor used for certain advanced non-small cell lung cancers driven by a RET gene fusion. Treatment is selected using a validated tumour test and supervised by an experienced cancer specialist.
Pramipexole dihydrochloride monohydrate is a dopamine agonist. In adults, selected immediate-release tablets are licensed for Parkinson’s disease and moderate to severe idiopathic restless legs syndrome; selected prolonged-release tablets are licensed for Parkinson’s disease.
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.
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.