pholedrine pholedrine pholedrine (paredrinol, pulsotyl, veritol), also known as 4-hydroxy-n-methylamphetamine (4-hma), 4-hydroxymethamphetamine, and para-hydroxymethamphetamine, is a drug that stimulates the sympathetic nervous system. it is administered as a topical eye drop form for the purpose of dilating the pupil and can be used to diagnose horner's syndrome. pholedrineclinical dataroutes ofadministrationtopical (ocular)identifiers iupac name 4-phenol cas number370-14-9 ypubchem cid4655chemspider4494 yuniiay28o44jgdkeggd08370 ychebichebi:134798chemblchembl2008672echa infocard100.006.114 chemical and physical dataformulac10h15nomolar mass165.236 g·mol−13d model (jsmol)interactive image smiles oc1ccc(cc1)cc(nc)c inchi inchi=1s/c10h15no/c1-8(11-2)7-9-3-5-10(12)6-4-9/h3-6,8,11-12h,7h2,1-2h3 nkey:sbuqzkjeooqsbv-uhfffaoysa-n n ny (what is this?) (verify) 4-hydroxymethamphetamine is also a major metabolite of methamphetamine.