252 articles
Pipamazine
Pipamazine (Mornidine, CAS 84-04-8), a phenothiazine antiemetic introduced in 1959 for nausea and vomiting; withdrawn by the US FDA in July 1969 for lack of proof of efficacy and safety in pregnant women.
Piperidolate
Piperidolate (Dactil) is a racemic tertiary amine antimuscarinic antispasmodic, ATC A03AA30, C21H25NO2, CAS 82-98-4, approved in Japan in 1967 for spasm and premature labor, banned in US racing.
Pirbuterol
Pirbuterol (Maxair, CP-24314-1) is a short-acting beta2-agonist bronchodilator with a pyridine ring replacing salbutamol's benzene ring; FDA-approved 1986 as a 200-microgram metered-dose inhaler, later discontinued.
Pirfenidone
Pirfenidone (Esbriet, Pirespa) is an oral antifibrotic drug for idiopathic pulmonary fibrosis, first approved in Japan in 2008, dosed 801 mg three times daily, slowing FVC decline with nausea, rash, and photosensitivity as common adverse effects.
Plecanatide
Plecanatide (Trulance) is a 16-amino-acid uroguanylin analog and guanylate cyclase-C agonist, FDA-approved in 2017 at 3 mg once daily for adult chronic idiopathic constipation and IBS-C, with diarrhea as the main adverse effect.
Pranlukast
Pranlukast (Onon, ONO-1078, SB 205312) is an oral leukotriene receptor antagonist blocking CysLT1; the first LTRA marketed (Japan, 1995), used mainly in Japan for asthma and allergic rhinitis, dose 225 mg twice daily.
Preparation H
Preparation H, an American hemorrhoid treatment brand first sold in 1949 and now owned by Haleon, offers ointments, creams, suppositories, wipes, and sprays with phenylephrine, pramoxine, lidocaine, and witch hazel.
Probiotic therapy
Probiotic therapy is the administration of live microorganisms, most often lactic acid bacteria, bifidobacteria, or the yeast Saccharomyces boulardii, to prevent or treat gastrointestinal conditions.
Procaterol
Procaterol (Meptin) is a selective short-acting beta2-adrenergic agonist bronchodilator for asthma and COPD, synthesized by Otsuka in 1973, given orally (50-100 mcg twice daily) or inhaled (20 mcg), with a 4.2-hour half-life.
Proglumide
Proglumide (Milid, Ulcutin) is a racemic glutaramic acid derivative and nonselective CCK1R/CCK2R antagonist, formerly marketed for peptic ulcer and now studied for opioid-sparing pain therapy and orphan cancer indications.
Propantheline
Propantheline (Pro-Banthine) is a synthetic quaternary ammonium antimuscarinic approved by the FDA in 1953, used as adjunctive peptic ulcer therapy and for hyperhidrosis; US brand discontinued.
Protokylol
Protokylol (Caytine, Ventaire) is a beta-2 adrenergic receptor agonist and isoproterenol derivative used as a bronchodilator in Europe and the US; its 2 mg oral tablet product was approved in 1982 and is discontinued.
Proton-pump inhibitor
Proton-pump inhibitors (PPIs), including omeprazole and esomeprazole, are drugs that irreversibly block the gastric H+/K+-ATPase proton pump to treat GERD, peptic ulcers, and H. pylori infection, with known long-term risks.
Prucalopride
Prucalopride (Resolor, Motegrity) is a selective 5-HT4 receptor agonist taken once daily for chronic constipation when laxatives fail; EU approval 2009, US 2018, NICE-recommended for women after two laxative classes fail.
Qirui Weishu capsules
Qirui Weishu capsules (七蕊胃舒胶囊), a Chinese class 1.1 innovative TCM by Jianmin Pharmaceutical Group, approved 31 December 2021 for epigastric pain in chronic non-atrophic gastritis with erosion, damp-heat stasis syndrome; entered China's 2022 national reimbursement list.
Rabeprazole
Rabeprazole (Aciphex) is a proton pump inhibitor for GERD, ulcers, H. pylori eradication, and Zollinger-Ellison syndrome, distinguished by mainly non-enzymatic metabolism, low CYP2C19 dependence, and low drug-interaction risk.
Racecadotril
Racecadotril (acetorphan), an enkephalinase-inhibitor prodrug converted to thiorphan, is an antisecretory antidiarrhoeal used with oral rehydration; approved in France in 1992, evidence in children is mixed.
Ramosetron
Ramosetron (YM060, Nasea, Irribow) is a Japanese-developed selective 5-HT3 receptor antagonist antiemetic with a 9-hour half-life, used against postoperative and chemotherapy-induced nausea and vomiting and, in Asia, IBS-D.
Ranitidine
Ranitidine (Zantac) is an H2 receptor antagonist for GERD, peptic ulcers, and Zollinger-Ellison syndrome. Withdrawn in 2020 over NDMA impurity formation during storage; FDA approved a reformulated version in November 2025.
RBx-10017609
RBx-10017609 (RBX 10017609) was an oral dual MMP-9/MMP-12 inhibitor developed by Ranbaxy with GSK for COPD; it completed Phase 1 safety studies and a 12-week Phase 2 proof-of-concept trial at 200 mg BID before being discontinued.
Rebamipide
Rebamipide (OPC-12759, Mucosta) is a quinolinone gastroprotective anti-ulcer drug from Otsuka, launched in Japan in 1990, also approved as 2% ophthalmic suspension for dry eye; it induces prostaglandins and scavenges radicals.
Recreational use of dextromethorphan
Recreational use of dextromethorphan, also called robotripping or DXM abuse, is taking supra-therapeutic doses of the OTC cough suppressant dextromethorphan for NMDA-mediated dissociative and hallucinatory effects, concentrated among adolescents and marked by a 2006 US poison-report peak.
Renzapride
Renzapride (BRL 24924, ATL-1251) is a substituted benzamide, full 5-HT4 agonist and 5-HT3/5-HT2b antagonist developed by Alizyme for IBS-C; Phase III efficacy was marginal and development was discontinued.
Revefenacin
Revefenacin (Yupelri, TD-4208) is a once-daily, nebulized long-acting muscarinic antagonist approved by the FDA in November 2018 for COPD maintenance, the only once-daily nebulized LAMA, dosed 175 mcg/3 mL via standard jet nebulizer.
Roflumilast
Roflumilast (Daxas, Daliresp, Zoryve) is a selective PDE4 inhibitor; oral 500 µg daily reduces COPD exacerbations in severe chronic bronchitis, and topical 0.3% formulations treat plaque psoriasis, atopic dermatitis, and seborrheic dermatitis.
Rolapitant
Rolapitant (Varubi), an oral NK1 receptor antagonist approved by the FDA in 2015, prevents delayed chemotherapy-induced nausea and vomiting; single 180 mg dose, ~176-hour half-life, no CYP3A4 inhibition, moderate CYP2D6 inhibitor.
Rosiptor
Rosiptor (AQX-1125) is an investigational oral drug that activates the enzyme SHIP1, developed by Aquinox Pharmaceuticals and discontinued after phase 2 and 3 trials failed.
SATWAVPP trial
SATWAVPP (NCT04716868): Mexican randomized double-blind trial comparing Agave tequilana blue-variety fructans (Predilife) with psyllium plantago for functional constipation; 79 patients, 8 weeks, similar responder rates across four arms.
Secretin synthetic human
Secretin synthetic human (ChiRhoStim, RG1068) is a synthetic 27-amino-acid copy of the human gut hormone secretin, FDA approved in 2004 to diagnose pancreatic exocrine dysfunction and gastrinoma and to aid ERCP; ineffective for autism.
Seladelpar
Seladelpar (Livdelzi) is a PPAR-delta agonist, 10 mg daily oral capsule for primary biliary cholangitis with inadequate UDCA response or intolerance; FDA accelerated approval August 2024, MHRA approval January 2025, NICE recommended 2026.