2799 T3D2757 Terfenadine Terfenadine is only found in individuals that have used or taken this drug. In the U.S., Terfenadine was superseded by fexofenadine in the 1990s due to the risk of cardiac arrhythmia caused by QT interval prolongation.Terfenadine competes with histamine for binding at H1-receptor sites in the GI tract, uterus, large blood vessels, and bronchial muscle. This reversible binding of terfenadine to H1-receptors suppresses the formation of edema, flare, and pruritus resulting from histaminic activity. As the drug does not readily cross the blood-brain barrier, CNS depression is minimal. 50679-08-8 5405 C32H41NO2 471.313730 White powder. 147°C 0.0963 mg/L (at 25°C) Oral. On the basis of a mass balance study using 14C labeled terfenadine the oral absorption of terfenadine was estimated to be at least 70% Terfenadine competes with histamine for binding at H1-receptor sites in the GI tract, uterus, large blood vessels, and bronchial muscle. This reversible binding of terfenadine to H1-receptors suppresses the formation of edema, flare, and pruritus resulting from histaminic activity. As the drug does not readily cross the blood-brain barrier, CNS depression is minimal. Terfenadine is a prodrug, generally completely metabolized to the active form fexofenadine in the liver by the enzyme cytochrome P450 CYP3A4 isoform. Due to its near complete metabolism by the liver immediately after leaving the gut, terfenadine normally is not measurable in the plasma. (Wikipedia) Half Life: 3.5 hours LD50: 5000 mg/kg (Oral, mouse) No indication of carcinogenicity to humans (not listed by IARC). For the treatment of allergic rhinitis, hay fever, and allergic skin disorders. Cardiotoxic at higher doses. In larger plasma concentrations, it may lead to toxic effects on the heart's rhythm (e.g. ventricular tachycardia and torsades de pointes). (Wikipedia) Mild (e.g., headache, nausea, confusion), but adverse cardiac events including cardiac arrest, ventricular arrhythmias including torsades de pointes and QT prolongation have been reported. in cases of overdosage, cardiac monitoring for at least 24 hours is recommended and for as long as QTc is prolonged, along with standard measures to remove any unabsorbed drug. Treatment of the signs and symptoms of overdosage should be symptomatic and supportive after the acute stage. (L1712) 2009-07-21T20:26:39Z 2026-05-14T16:35:59Z Terfenadine C07463 119569 Terfenadine DB00342 true CC(C)(C)C1=CC=C(C=C1)C(O)CCCN1CCC(CC1)C(O)(C1=CC=CC=C1)C1=CC=CC=C1 C32H41NO2 InChI=1S/C32H41NO2/c1-31(2,3)26-18-16-25(17-19-26)30(34)15-10-22-33-23-20-29(21-24-33)32(35,27-11-6-4-7-12-27)28-13-8-5-9-14-28/h4-9,11-14,16-19,29-30,34-35H,10,15,20-24H2,1-3H3 GUGOEEXESWIERI-UHFFFAOYSA-N 471.6734 471.313729561 Exogenous Solid 7.1 HMDB14486 CHEMBL17157 5212 <p>Timothy G. Fawcett, Christian T. Goralski, David W. Ziettlow, &#8220;Preparation of polymorphically pure terfenadine.&#8221; U.S. Patent US4742175, issued April, 1975.</p> CHEM002176 DTXSID2023642 NS00006817 1-(4-tert-butylphenyl)-4-[4-(hydroxydiphenylmethyl)piperidin-1-yl]butan-1-ol 43.7 146.26740000000007 56.45178022243013 9 3 2 13.197068104137273 9.02298591531735 1 4 5.89 -6.01 4.58e-04 g/l