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Pentoxifylline is a peripheral vasodilator that alters blood-flow properties in small vessels. Selected UK products are licensed for peripheral vascular disease, including intermittent claudication and ischaemic rest pain, although evidence for improving walking ability in intermittent claudication is uncertain.
Peppermint oil is a herbal antispasmodic that relaxes bowel muscle. Gastro-resistant capsules are used mainly to relieve abdominal cramps, bloating and wind associated with irritable bowel syndrome (IBS).
Perampanel is a prescription anti-seizure treatment that reduces excitatory signalling in the brain. Selected UK products are licensed alongside other anti-seizure treatments for certain focal and generalised seizures.
Perflutren is an ultrasound contrast agent containing tiny gas-filled human-albumin microspheres. It is injected into a vein during an echocardiogram when ordinary images do not show the heart's left chamber and wall movement clearly enough.
Pericyazine is a first-generation phenothiazine antipsychotic with marked sedative effects. In adults, it is mainly used for schizophrenia and other psychoses, or as an adjunct in short-term management of severe agitation, anxiety or dangerously impulsive behaviour.
Permethrin is a topical synthetic pyrethroid that kills scabies mites and lice by disrupting their nerve-cell function. The selected cream is licensed for scabies in adults and children from 2 months, and for crab lice in adults.
Pertuzumab is a targeted monoclonal antibody used for HER2-positive breast cancer. It is usually combined with trastuzumab and chemotherapy for selected early, locally advanced or metastatic disease.
Pertuzumab and trastuzumab are targeted monoclonal antibodies that attach to different parts of the HER2 protein. The fixed combination is used with chemotherapy for selected adults with HER2-positive early or advanced breast cancer.
Phenelzine sulfate is an irreversible monoamine oxidase inhibitor (MAOI) antidepressant. It is licensed for certain depressive illnesses, particularly where anxiety or phobic features are prominent or other antidepressants have not worked.
Phenindione is an oral vitamin K antagonist anticoagulant that reduces the formation of several clotting factors. It is licensed to prevent or treat specified blood clots and requires regular blood-test monitoring.
Phenobarbital is a long-acting barbiturate antiseizure treatment. The selected elixir is licensed for epilepsy other than absence seizures. It can cause sedation and has many clinically important interactions.
Phenobarbital sodium is a long-acting barbiturate antiseizure treatment licensed for epilepsy other than absence seizures. It can cause sedation.
Phenol is a sclerosing agent with local pain-relieving properties. The selected oily injection is used by clinicians to treat internal haemorrhoids, causing them to scar and shrink.
Phenoxybenzamine hydrochloride is a long-acting, non-selective alpha blocker used by specialist teams to control hypertensive episodes caused by phaeochromocytoma, including preparation for tumour surgery.
Phenylephrine hydrochloride is a sympathomimetic that narrows blood vessels. Depending on formulation, it is used for nasal congestion, pupil dilation during eye procedures, or low blood pressure during anaesthesia.
This combination is an ophthalmic insert that temporarily enlarges the pupil before eye surgery or diagnostic examination when a single pupil-dilating agent is unlikely to be sufficient.
Phenytoin is an antiseizure treatment that reduces the spread of abnormal electrical activity in the brain. It is mainly used for focal and tonic-clonic seizures, including seizures associated with neurosurgery or severe head injury.
Phenytoin sodium is an antiseizure treatment that helps prevent abnormal electrical activity from spreading through the brain. Oral products are mainly used for selected focal and tonic-clonic seizures, while injections are reserved for specific hospital indications.
Pholcodine monohydrate was a centrally acting opioid cough suppressant for short-term relief of dry, non-productive cough. All pholcodine-containing medicines were withdrawn from the UK market in March 2023 because benefits did not outweigh a very small increased risk of severe allergic reactions to certain medicines used during general anaesthesia.
Phytomenadione is vitamin K1, which the liver needs to produce proteins involved in blood clotting. It is used to prevent or treat vitamin K deficiency bleeding in babies and to reverse coumarin anticoagulants such as warfarin when clinically required.
Pilocarpine hydrochloride activates muscarinic receptors. Tablets stimulate saliva and tears in specific dry-mouth conditions, while eye drops constrict the pupil and help lower pressure inside the eye.
Pilocarpine nitrate is a direct-acting parasympathomimetic eye drop that constricts the pupil. The selected UK product is used by eye-care professionals to reverse weaker pupil-dilating drops and in emergency glaucoma treatment.
Pimecrolimus is a non-steroid anti-inflammatory cream for mild or moderate atopic eczema. It is usually considered when topical corticosteroids are unsuitable, ineffective or poorly tolerated, including for sensitive areas such as the face and neck.
Pimozide is a first-generation antipsychotic that reduces dopamine signalling in the brain. The selected product is licensed for chronic schizophrenia and certain other psychoses, including persistent paranoid or single-theme delusional states.
Pioglitazone hydrochloride is an oral thiazolidinedione that makes the body more responsive to insulin. It is licensed for selected adults with type 2 diabetes when diet, physical activity and other glucose-lowering treatment have not provided sufficient control or metformin is unsuitable.
Piperacillin + tazobactam combines an extended-spectrum penicillin antibiotic with a beta-lactamase inhibitor. It is given into a vein, usually in hospital or through a supervised outpatient intravenous antibiotic service, for serious bacterial infections.
Combines a broad-spectrum penicillin antibacterial with a beta-lactamase inhibitor. It is given into a vein for serious bacterial infections in a clinically supervised setting.
Pirfenidone is an antifibrotic treatment for adults with idiopathic pulmonary fibrosis (IPF). It can slow worsening of lung function but does not cure IPF or reverse existing scarring.
Piroxicam is a prescription non-steroidal anti-inflammatory drug (NSAID) that reduces pain and inflammation. Oral piroxicam is reserved for symptomatic relief of osteoarthritis, rheumatoid arthritis or ankylosing spondylitis when another NSAID is not a better option.
Pitolisant hydrochloride is a wake-promoting treatment that increases histamine signalling in the brain. It is used for narcolepsy with or without cataplexy and, in selected adults, persistent excessive daytime sleepiness associated with obstructive sleep apnoea.
Pixantrone dimaleate is a cytotoxic anticancer treatment used alone in adults whose aggressive non-Hodgkin B-cell lymphoma has returned repeatedly or has not responded to previous chemotherapy.
Pizotifen malate is a prescription-only preventive treatment for recurrent migraine and cluster headache. It is taken regularly to reduce future headaches and does not relieve an attack already under way.
Plerixafor is a stem-cell mobilisation treatment used with granulocyte-colony stimulating factor (G-CSF). It releases blood-forming stem cells from bone marrow into the bloodstream so they can be collected for a person's own stem-cell transplant.
Pneumococcal vaccines are inactivated vaccines that help the immune system recognise selected types of Streptococcus pneumoniae. They reduce the risk of serious infections including pneumonia, meningitis and sepsis, particularly in older people and those with certain health conditions.
Podophyllotoxin is a prescription-only topical treatment that destroys genital wart tissue by stopping affected cells from dividing. The selected products are licensed for external genital warts on the penis or external female genital area.
Polatuzumab vedotin is an antibody–drug conjugate that targets CD79b on B cells and delivers a cell-killing agent inside them. It is used with other cancer treatments for adults with diffuse large B-cell lymphoma (DLBCL), either when newly diagnosed or in certain relapsed or refractory cases.
Polygeline is a gelatin-derived colloid solution given by intravenous infusion in hospital to expand circulating plasma volume, including for initial treatment of hypovolaemic shock.
Pomalidomide is an immunomodulatory anticancer treatment for adults with previously treated multiple myeloma. It is used with dexamethasone and, in some circumstances, bortezomib.
Ponatinib is a targeted tyrosine kinase inhibitor used by specialist teams to treat certain adults with chronic myeloid leukaemia or Philadelphia-chromosome-positive acute lymphoblastic leukaemia. It is generally reserved for disease with specified resistance, intolerance or the T315I mutation.
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.