Gastrointestinal and respiratory drugs

Acefylline

Acefylline (acephylline, acepifylline), an N-7-substituted theophylline xanthine bronchodilator (C9H10N4O4, CAS 652-37-9) for asthma and bronchitis; European Pharmacopoeia-listed, no separate FDA approval, efficacy questioned since 1978.

Acetylcysteine

Acetylcysteine (N-acetylcysteine, NAC; Mucomyst, Fluimucil, Acetadote) is a sulfhydryl mucolytic drug, patented 1960, and the standard antidote for acetaminophen overdose, dosed 300 mg/kg IV.

Aclidinium

Aclidinium bromide (Tudorza Pressair, Eklira Genuair; with formoterol, Duaklir Pressair) is an inhaled long-acting muscarinic antagonist for twice-daily maintenance bronchodilator treatment of COPD, delivered via the Genuair/Pressair dry powder inhaler.

Acotiamide

Acotiamide (Acofide, Z-338), Zeria's acetylcholinesterase inhibitor prokinetic approved in Japan in 2013 for functional dyspepsia; 100 mg three times daily before meals for postprandial fullness, bloating, early satiation.

Admilparant

Admilparant (BMS-986278) is Bristol Myers Squibb's oral LPA1 receptor antagonist for pulmonary fibrosis; phase 2 showed slowed FVC decline in IPF and PPF, and phase 3 ALOFT-IPF met its primary endpoint at 60 mg.

AK3280

AK3280 is an oral antifibrotic drug candidate by Shanghai Ark Biopharmaceutical for idiopathic pulmonary fibrosis, derived from pirfenidone, with positive Phase 2 results in 2025.

Alizapride

Alizapride (CAS 59338-93-1), a substituted benzamide dopamine D2 antagonist antiemetic related to metoclopramide; ATC A03FA05, 3-hour half-life, renal elimination; sold nationally as Plitican, Litican, Vergentan, not EMA/FDA approved.

Alka-Seltzer

Alka-Seltzer, Bayer's effervescent OTC brand introduced in 1931: original tablets combine aspirin 325 mg, citric acid, and sodium bicarbonate for heartburn, upset stomach, and pain; distinct from Alka-Seltzer Cold (formerly Plus) cold/flu line.

Almitrine

Almitrine, sold as Vectarion and Armanor, is a respiratory stimulant for chronic respiratory failure in COPD, withdrawn across the EU in 2013 after causing peripheral neuropathy and weight loss.

Alosetron

Alosetron (Lotronex), a 5-HT3 antagonist for severe IBS-D in women; approved 2000, withdrawn 2000, reintroduced 2002 under REMS; risks include ischemic colitis and severe constipation.

Alvimopan

Alvimopan (Entereg), a peripherally acting mu-opioid receptor antagonist approved by the FDA in 2008, accelerates gastrointestinal recovery after bowel resection; strong evidence in open surgery, uncertain benefit in minimally invasive procedures.

Ambroxol

Ambroxol, a mucolytic metabolite of bromhexine marketed since 1973, thins airway mucus and shows anti-inflammatory, antioxidant, surfactant-stimulating, and local anesthetic actions; studied for COPD, sore throat, and Gaucher/Parkinson disease.

Anaprazole sodium

Anaprazole sodium (安奈拉唑钠, trade name Anjiuwei) is a Chinese-developed proton pump inhibitor approved by the NMPA in June 2023 for duodenal ulcer, non-inferior to rabeprazole in phase III trials, with CYP2C19-independent metabolism.

Anisodamine

Anisodamine (山莨菪碱, code 654; synthetic racemate 654-2) is a tropane alkaloid M-anticholinergic from Anisodus tanguticus, isolated in China in the 1960s and used for smooth-muscle spasm, microcirculatory shock, and organophosphate poisoning.

Anisotropine

Anisotropine methylbromide (octatropine methylbromide), a quaternary ammonium antimuscarinic tropane derivative once sold as Valpin 50 for peptic ulcer; discontinued, replaced by more effective agents.

Antacid

Antacid: over-the-counter medicines (aluminum, magnesium, calcium salts such as calcium carbonate, aluminum hydroxide) that neutralize stomach acid to relieve heartburn and indigestion; distinct from acid-suppressing H2 blockers and PPIs.

Antiemetic

Antiemetic: drug class preventing or treating nausea and vomiting. Includes 5-HT3 antagonists (ondansetron), dopamine antagonists (metoclopramide), NK1 antagonists, antihistamines, steroids; used in chemotherapy, surgery, pregnancy, gastroenteritis.

Aprepitant

Aprepitant (Emend) is a substance P/neurokinin-1 receptor antagonist antiemetic first approved in 2003 to prevent chemotherapy-induced and postoperative nausea and vomiting; oral 125/80/80 mg dosing, CYP3A4 interactions, IV Aponvie since 2022.

Arbaclofen placarbil

Arbaclofen placarbil (XP19986) is a transported prodrug of R-baclofen developed by XenoPort for GERD and spasticity; abandoned after failed GERD trials and terminated MS development in 2013, later licensed to Indivior.

Arformoterol

Arformoterol (Brovana) is the (R,R)-enantiomer of formoterol, a long-acting beta2-agonist nebulized twice daily (15 mcg) for COPD maintenance; FDA-approved October 6, 2006, not indicated for asthma, brand discontinued with generics since 2021.

Asimadoline

Asimadoline (EMD-61753) is an investigational peripherally selective kappa-opioid receptor agonist for IBS-D; potent KOR agonist (IC50 1.2 nM), low CNS penetration, no overall IBS efficacy in trials, subgroup benefit only.

ATB102, aryl hydrocarbon receptor (AhR) agonist for ulcerative colitis

ATB102 (YUQ-A1007) is Allianthera's oral, gut-enriched aryl hydrocarbon receptor agonist in phase 1 trials for refractory moderate-to-severe ulcerative colitis; Dr. Falk Pharma licensed worldwide rights in July 2025, excluding Greater China.

Aviptadil

Aviptadil (RLF-100, ZYESAMI), a synthetic 28-amino-acid form of vasoactive intestinal peptide, is a lung-protective, anti-inflammatory peptide drug tested for ARDS and COVID-19 respiratory failure; large trials found no survival benefit.

AYUSH Ghutti

AYUSH Ghutti: CCRAS Ayurvedic pediatric formulation (Patent 193336, NRDC) to prevent diarrhoea and fever in children; seven ingredients, dose 1-3 ml twice daily; technology transferred to industry.

AYUSH-A

AYUSH-A is a coded Ayurvedic formulation developed by CCRAS, India's Ayurveda research council, for bronchial asthma (Tamaka Shwasa); evaluated in randomized placebo controlled trials with AIIMS New Delhi and at three regional institutes, it remains in CCRAS's drug development pipeline.