Clinical data
Trade namesHytrin, Zayasel, others
License data
ATC code
Legal status
Legal status
Pharmacokinetic data
Protein binding90–94%
Elimination half-life12 hours
  • (RS)-6,7-Dimethoxy-2-[4-(tetrahydrofuran-2-ylcarbonyl)piperazin-1-yl]quinazolin-4-amine
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.118.191 Edit this at Wikidata
Chemical and physical data
Molar mass387.440 g·mol−1
3D model (JSmol)
  • O=C(N3CCN(c2nc1cc(OC)c(OC)cc1c(n2)N)CC3)C4OCCC4
  • 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) checkY

Terazosin, sold under the brand name Hytrin among others, is a medication used to treat symptoms of an enlarged prostate and high blood pressure.[1] For high blood pressure, it is a less preferred option.[1] It is taken by mouth.[1]

Common side effects include dizziness, headache, tiredness, swelling, nausea, and low blood pressure with standing.[1] Severe side effects may include priapism and low blood pressure.[1] Prostate cancer should be ruled out before starting treatment.[1] It is an alpha-1 blocker and works by relaxing blood vessels and the opening of the bladder.[1] It is used in the treatment of benign prostatic hyperplasia and the frequent urination that occurs in patients with that indication.

Terazosin was patented in 1975 and came into medical use in 1985.[2] It is available as a generic medication.[3] In 2018, it was the 198th most commonly prescribed medication in the United States, with more than 2 million prescriptions.[4][5]


It is available in 1 mg, 2 mg, 5 mg or 10 mg doses.[6]


Terazosin synthesis:[7]
Terazosin synthesis:[7]

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).


  1. ^ a b c d e f g "Terazosin Hydrochloride Monograph for Professionals". Drugs.com. American Society of Health-System Pharmacists. Retrieved 17 March 2019.
  2. ^ Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 455. ISBN 9783527607495.
  3. ^ British national formulary : BNF 76 (76 ed.). Pharmaceutical Press. 2018. p. 768. ISBN 9780857113382.
  4. ^ "The Top 300 of 2021". ClinCalc. Retrieved 18 February 2021.
  5. ^ "Terazosin - Drug Usage Statistics". ClinCalc. Retrieved 18 February 2021.
  6. ^ "Terazosin Hydrochloride Capsule". DailyMed. National Library of Medicine, National Institutes of Health.
  7. ^ US 4026894, Winn M, Kyncl J, Dunnigan DA, Jones PH, issued 31 May 1977, assigned to Abbott