fasedienol fasedienol fasedienol (inn; developmental code names ph94b and aloradine), also known as 4-androstadienol or as 4,16-androstadien-3β-ol, is a pherine which is under development by vistagen therapeutics in a nasal spray formulation (prn) for the acute treatment of social anxiety disorder. it is also being investigated by vistagen therapeutics for the treatment of generalized anxiety disorder (gad) and post-traumatic stress disorder (ptsd). the pherine is a positional isomer of the endogenous pheromone androstadienol (5-androstadienol or 5,16-androstadien-3β-ol). as of 2020, it is in phase iii clinical trials for social anxiety disorder. fasedienolclinical dataother namesph94b; aloradine; 4-androstadienol; 3β-androsta-4,16-dien-3-ol, androsta-4,16-dien-3β-ol; androstadienolroutes ofadministrationintranasalatc codenoneidentifiers iupac name (3s,8s,9s,10r,13r,14s)-10,13-dimethyl-2,3,6,7,8,9,11,12,14,15-decahydro-1h-cyclopentaphenanthren-3-ol cas number23062-06-8pubchem cid9925482drugbankdb04968chemspider8101117uniidtw1nj7ijhkeggd12524 ychemical and physical dataformulac19h28omolar mass272.432 g·mol−13d model (jsmol)interactive image smiles c12cc3(1cc=c2)ccc4=c(cc34c)o inchi inchi=1s/c19h28o/c1-18-9-3-4-16(18)15-6-5-13-12-14(20)7-11-19(13,2)17(15)8-10-18/h3,9,12,14-17,20h,4-8,10-11h2,1-2h3/t14-,15-,16-,17-,18-,19-/m0/s1key:nyvfcepouvgtnp-dykiifrcsa-n fasedienol lacks affinity for steroid hormone receptors and has instead been found to directly activate isolated human vomeronasal receptor cells at nanomolar concentrations (ec50 = 200 nm). the pheromone androstenol has been found to act as a potent positive allosteric modulator of the gabaa receptor, and it has been proposed that this action may mediate its pheromone effects. it produces anxiolytic-like effects in animals. androstadienol, androstadienone, and androstenone, all of which are also pheromones, have been found to be converted into androstenol, and as such, it may be responsible for their pheromone effects. as fasedienol is very closely related structurally to androstadienol, it might be converted into androstenol similarly and hence potentiation of the gabaa receptor could contribute to its mechanism of action.