Active Ingredients A to Z

Pancrelipase Pancrelipase is a pancreatic enzyme replacement that helps digest fat, protein and starch in people whose pancreas does not make enough of its own. High doses have been linked to a serious bowel narrowing called fibrosing colonopathy, so the prescribed dose should never be exceeded. 1 medicine View → Pancrelipase Paracetamol Paracetamol (acetaminophen) relieves pain and fever and is hidden in many combination cold and flu remedies; taking more than the recommended dose can cause serious, sometimes fatal liver damage. 1 medicine View → Paracetamol Paroxetine Paroxetine is an SSRI antidepressant used for depression and anxiety disorders. It causes the most severe discontinuation symptoms of any SSRI if stopped abruptly, so the dose must always be tapered down slowly. 2 medicines View → Paroxetine Pentosan Polysulfate Pentosan polysulfate is used to relieve bladder pain and urgency in interstitial cystitis. Long-term use has been linked to a slowly progressive eye disease called pigmentary maculopathy that can cause permanent vision loss, so regular eye examinations are essential. 1 medicine View → Pentosan Polysulfate Perindopril Perindopril is an ACE inhibitor used to treat high blood pressure and heart failure and to protect the heart after a heart attack. It must not be used in pregnancy, since it can seriously harm the baby, and it can rarely cause angioedema, a sudden swelling of the face and throat needing emergency care. 2 medicines View → Perindopril Phenazopyridine Phenazopyridine is a short-term urinary analgesic that numbs bladder and urethra pain but does not treat infection, and it turns urine orange-red, which can stain clothing and contact lenses. 1 medicine View → Phenazopyridine Phenytoin Phenytoin is an anticonvulsant used mainly for epilepsy. It has a narrow therapeutic index, so small dose changes can cause toxicity, and regular blood-level monitoring is essential. 1 medicine View → Phenytoin Pimecrolimus Pimecrolimus is a topical calcineurin inhibitor for mild-to-moderate eczema that carries a boxed warning for a rare risk of skin cancer and lymphoma with long-term use, so it should be used for the shortest time needed and kept away from strong sun exposure. 1 medicine View → Pimecrolimus Pioglitazone Pioglitazone is a thiazolidinedione for type 2 diabetes that can cause fluid retention and must be avoided in heart failure, and it carries a caution around long-term bladder-cancer risk. 2 medicines View → Pioglitazone Piracetam Piracetam is a nootropic used mainly as an add-on treatment for cortical myoclonus, and because it reduces platelet clumping, it raises the risk of bleeding when combined with blood thinners or before surgery. 1 medicine View → Piracetam Pirfenidone Pirfenidone is an antifibrotic for idiopathic pulmonary fibrosis that requires regular liver-function blood tests and strict sun protection, because it can cause both liver injury and severe photosensitivity reactions. 1 medicine View → Pirfenidone Piroxicam Piroxicam is an NSAID that carries the highest risk of stomach and intestinal bleeding among commonly used NSAIDs, so many guidelines restrict it to second-line use and short courses. 1 medicine View → Piroxicam Pitavastatin Pitavastatin is a statin that lowers LDL cholesterol, and its main safety risk is muscle injury (myopathy), which can progress to life-threatening rhabdomyolysis, so unexplained muscle pain or dark urine needs urgent attention. 1 medicine View → Pitavastatin Pramipexole Pramipexole is a dopamine agonist for Parkinson's disease and restless legs syndrome that can cause sudden sleep attacks without warning and impulse-control problems such as compulsive gambling, shopping, or hypersexuality. 1 medicine View → Pramipexole Praziquantel Praziquantel is an antiparasitic that treats both tapeworm and fluke infections, including schistosomiasis, and when used for a brain tapeworm infection (neurocysticercosis) it's usually combined with a corticosteroid, because killing the parasites can trigger seizures or brain swelling. 1 medicine View → Praziquantel Prazosin Prazosin is an alpha-1 blocker used for high blood pressure, urinary symptoms of an enlarged prostate, and PTSD-related nightmares; its first dose can cause a sudden drop in blood pressure and fainting, so it is taken at bedtime. 1 medicine View → Prazosin Prednisolone Prednisolone is a corticosteroid used for asthma attacks, severe allergies, autoimmune flares and other inflammatory conditions; after more than a few weeks of use it must be tapered off gradually, never stopped abruptly, to avoid a dangerous adrenal crisis. 2 medicines View → Prednisolone Primidone Primidone is an anticonvulsant that the body converts into phenobarbital, used for seizures and essential tremor; it must never be stopped abruptly, since sudden withdrawal can trigger seizures even in people without epilepsy. 1 medicine View → Primidone Probenecid Probenecid is a uricosuric medicine used to lower uric acid and prevent gout attacks and kidney stones; it blocks the kidneys from clearing certain other drugs, most seriously methotrexate, which can build up to toxic levels if the two are combined. 1 medicine View → Probenecid Prochlorperazine Prochlorperazine is a phenothiazine used to control nausea, vomiting and vertigo, and in higher doses for psychotic symptoms; it can cause extrapyramidal reactions and, rarely, life-threatening neuroleptic malignant syndrome, which needs emergency care. 1 medicine View → Prochlorperazine Procyclidine Procyclidine is an anticholinergic medicine used for Parkinson's disease and drug-induced movement side effects; it must be avoided in untreated angle-closure glaucoma and urinary retention, which its anticholinergic action can dangerously worsen. 1 medicine View → Procyclidine Progesterone Progesterone is a hormone used to support the uterine lining, prevent early pregnancy loss, treat absent periods and balance estrogen in hormone therapy; any unexplained vaginal bleeding needs urgent medical review, and the hormone raises the risk of blood clots. 1 medicine View → Progesterone Propranolol Propranolol is a non-selective beta-blocker used for high blood pressure, angina, tremor, migraine prevention and situational anxiety; it must never be stopped abruptly, especially in people with heart disease, since sudden withdrawal can trigger rebound chest pain or a heart attack. 2 medicines View → Propranolol Prucalopride Prucalopride is a selective 5-HT4 receptor agonist that stimulates gut movement to treat chronic constipation; it must not be used if you have a bowel obstruction or perforation. 1 medicine View → Prucalopride Pyridostigmine Pyridostigmine is a reversible acetylcholinesterase inhibitor used mainly for myasthenia gravis; taking too much can cause a cholinergic crisis with worsening weakness and breathing difficulty. 1 medicine View → Pyridostigmine Pyridoxine Pyridoxine is vitamin B6, used to treat deficiency, some forms of anaemia, and pregnancy-related nausea; long-term high doses can cause nerve damage (peripheral neuropathy). 1 medicine View → Pyridoxine