homatropine methylbromide homatropine methylbromide homatropine methylbromide (inn; also known as methylhomatropine bromide) is a quaternary ammonium salt of methylhomatropine. it is a peripherally acting anticholinergic medication that inhibits muscarinic acetylcholine receptors and thus the parasympathetic nervous system. it does not cross the blood–brain barrier. it is used to effectively relieve intestinal spasms and abdominal cramps, without producing the adverse effects of less specific anticholinergics. it is used, in addition to papaverine, as a component of mild drugs that help "flush" the bile. homatropine methylbromideclinical dataother namesmethylhomatropine bromideatc codea03bb06 (who) identifiers iupac name (n,n-dimethyl-8-azoniabicyclooct-3-yl) 2-hydroxy-2-phenylacetate bromide cas number80-49-9pubchem cid6646drugbankdb00725chemspider6394 yunii68jrs2hc1ckeggd02070chemblchembl1200851comptox dashboard (epa)dtxsid4023127 echa infocard100.001.168 chemical and physical dataformulac17h24brno3molar mass370.287 g·mol−13d model (jsmol)interactive image smiles c1(c2ccc1cc(c2)oc(=o)c(c3=cc=cc=c3)o)c. inchi inchi=1s/c17h24no3.brh/c1-18(2)13-8-9-14(18)11-15(10-13)21-17(20)16(19)12-6-4-3-5-7-12;/h3-7,13-16,19h,8-11h2,1-2h3;1h/q+1;/p-1/t13-,14+,15+,16?; ykey:ztvikzxzylevol-mcoxgkprsa-n y (verify) certain preparations of drugs such as hydrocodone are mixed with a small, sub-therapeutic amount of homatropine methylbromide to discourage intentional overdose. contraindications untreated glaucoma myasthenia gravis severe heart failure thyrotoxicosis