3579 Terazosin Terazosin is a selective alpha 1 antagonist used for treatment of symptoms of prostate enlargement (BPH). It also acts to lower blood pressure, so it is a drug of choice for men with hypertension and prostate enlargement. It works by blocking the action of adrenaline on smooth muscle of the bladder and the blood vessel walls. 70024-40-7 5401 C19H25N5O4 459.188460 Terazosin is a white, crystalline substance, 273°C 29.7mg/mL Oral. Essentially completely absorbed in man (90% bioavailability). Terazosin selectively and competitively inhibits vascular postsynaptic alpha(1)-adrenergic receptors, resulting in peripheral vasodilation and a reduction of vascular resistance and blood pressure. Unlike the nonselective alph-adrenergic blockers phenoxybenzamine and phentolamine, terazosin does not block presynaptic alpha(2)-receptors and, hence, does not cause reflex activation of norepinephrine release to produce reflex tachycardia. Hepatic. One of the four metabolites identified (piperazine derivative of terazosin) has antihypertensive activity. Route of Elimination: Approximately 10% of an orally administered dose is excreted as parent drug in the urine and approximately 20% is excreted in the feces. Half Life: 12 hours LD50: 259.3mg/kg (parental-intravenous, Mouse) (A308) No indication of carcinogenicity to humans (not listed by IARC). Terazosin is indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH). There is a rapid response, with approximately 70% of patients experiencing an increase in urinary flow and improvement in symptoms of BPH when treated with terazosin. The long-term effects of terazosin on the incidence of surgery, acute urinary obstruction or other complications of BPH are yet to be determined. Terazosin tablets are also indicated for the treatment of hypertension. Terazosin tablets can be used alone or in combination with other antihypertensive agents such as diuretics or beta-adrenergic blocking agents. Hypotension, palpitations, postural hypotension, syncope, peripheral edema, weight gain, dyspnea, nasal congestion/rhinitis, impotence. Asthenia, postural hypotension, dizziness, somnolence, nasal congestion/rhinitis. Should overdosage of Terazosin lead to hypotension, support of the cardiovascular system is of first importance. Restoration of blood pressure and normalization of heart rate may be accomplished by keeping the patient in the supine position. If this measure is inadequate, shock should first be treated with volume expanders. If necessary, vasopressors should then be used and renal function should be monitored and supported as needed. Laboratory data indicate that Terazosin is highly protein bound; therefore, dialysis may not be of benefit. (L1712) 2009-07-30T17:59:10Z 2014-12-24T20:26:08Z Terazosin C07127 9445 Terazosin DB01162 true COC1=C(OC)C=C2C(=N)NC(=NC2=C1)N1CCN(CC1)C(=O)C1CCCO1 C19H25N5O4 InChI=1/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) InChIKey=VCKUSRYTPJJLNI-UHFFFAOYNA-N 387.4329 387.190654313 Exogenous Solid 1 CHEMBL611 5208 <p>K. S. Keshava Murthy, Gamini Weeratunga, Tianhao Zhou, Bhaskar Reddy Guntoori, &#8220;Process for the manufacture of intermediates suitable to make doxazosin, terazosin, prazosin, tiodazosin and related antihypertensive medicines.&#8221; U.S. Patent US5919931, issued September, 1986.</p>