terazosin terazosin terazosin, sold under the brand name hytrin among others, is a medication used to treat symptoms of an enlarged prostate and high blood pressure. for high blood pressure, it is a less preferred option. it is taken by mouth. terazosinclinical datatrade nameshytrin, zayasel, othersahfs/drugs.commonographmedlineplusa693046license data us dailymed: terazosin routes ofadministrationby mouthatc codeg04ca03 (who) legal statuslegal status us: ℞-only pharmacokinetic dataprotein binding90–94%elimination half-life12 hoursidentifiers iupac name (rs)-6,7-dimethoxy-2-quinazolin-4-amine cas number63590-64-7 ypubchem cid5401iuphar/bps7302drugbankdb01162 ychemspider5208 yunii8l5014xet7keggd08569 ychebichebi:9445 ychemblchembl611 ycomptox dashboard (epa)dtxsid3023639 echa infocard100.118.191 chemical and physical dataformulac19h25n5o4molar mass387.440 g·mol−13d model (jsmol)interactive image smiles o=c(n3ccn(c2nc1cc(oc)c(oc)cc1c(n2)n)cc3)c4occc4 inchi inchi=1s/c19h25n5o4/c1-26-15-10-12-13(11-16(15)27-2)21-19(22-17(12)20)24-7-5-23(6-8-24)18(25)14-4-3-9-28-14/h10-11,14h,3-9h2,1-2h3,(h2,20,21,22) ykey:vckusrytpjjlni-uhfffaoysa-n y (verify) common side effects include dizziness, headache, tiredness, swelling, nausea, and low blood pressure with standing. severe side effects may include priapism and low blood pressure. prostate cancer should be ruled out before starting treatment. it is an alpha-1 blocker and works by relaxing blood vessels and the opening of the bladder. terazosin was patented in 1975 and came into medical use in 1985. it is available as a generic medication. in 2020, it was the 211th most commonly prescribed medication in the united states, with more than 2 million prescriptions. a study by researchers from the university of edinburgh and the university of oxford, published in 2022, suggested that terazosin may have the potential to confer neuroprotection upon motor neurons in motor neuron disease, as a result of its ability to activate pgk1. synthesis terazosin synthesis: reaction of piperazine with 2-furoyl chloride followed by catalytic hydrogenation of the furan ring leads to 2. this, when heated in the presence of 2-chloro-6,7-dimethoxyquinazolin-4-amine (1) undergoes direct alkylation to terazosin (3).