• Molecular NameDexfenfluramine
  • SynonymD-Fenfluramine; Dexafenfluramine; Dexfenfluramina [Spanish]; Dexfenfluramine Hydrochloride; Dexfenfluraminum [Latin]; Dextrofenfluramine; L-Fenfluramine; Levofenfluramina [Spanish]; Levofenfluramine; Levofenfluramine [INN]; Levofenfluraminum [Latin]
  • Weight231.261
  • Drugbank_IDDB01191
  • ACS_NO458-24-2
  • Show 3D model
  • LogP (experiment)3.36
  • LogP (predicted, AB/LogP v2.0)3.43
  • pka10
  • LogD (pH=7, predicted)0.93
  • Solubility (experiment)N/A
  • LogS (predicted, ACD/Labs)(ph=7)0.38
  • LogSw (predicted, AB/LogsW2.0)0.67
  • Sw (mg/ml) (predicted, ACD/Labs)0.94
  • No.of HBond Donors1
  • No.of HBond Acceptors1
  • No.of Rotatable Bonds5
  • TPSA12.03
  • StatusFDA approved, US withdrawn
  • AdministrationN/A
  • PharmacologyA drug that was part of the Fen-Phen anti-obesity medication (the other drug being phentermine).
  • Absorption_value95.0
  • Absorption (description)Readily absorbed after oral administration and accumulates in the tissues.
  • Caco_2N/A
  • Bioavailability79.0
  • Protein binding36.0
  • Volume of distribution (VD)N/A
  • Blood/Plasma Partitioning ratio (D_blood)Plasma:whole blood ratio, about 0.74.
  • MetabollsmThe major metabolite in the blood is the N-desethyl derivative, norfenfluramine, which is active. It is also metabolised by oxidation to m-trifluoromethylbenzoic acid which is conjugated with glycine to form m-trifluoromethylhippuric acid.
  • Half life17~20 h
  • ExcretionThe rate of elimination is influenced by urinary pH and urinary flow. In acidic urine about 23% of a dose is excreted unchanged and about 17% as norfenfluramine in 48 h; the remainder consists of m-trifluoromethylhippuric acid; in alkaline urine about 2% is excreted as unchanged drug and norfenfluramine; when the urinary pH is not controlled, 3 to 10% may be excreted as unchanged drug and 3 to 14% as norfenfluramine. Up to 5% of a dose is eliminated in the faeces as fenfluramine and norfenfluramine.
  • Urinary ExcretionN/A
  • CleranceN/A
  • ToxicityIn adults the minimum lethal dose is probably in excess of 2 g but for young children as little as 200 mg may cause death. Toxic effects may be produced when the plasma concentration is greater than about 0.5 mg/L, and death has occurred at concentrations above 6 mg/L.
  • LD50 (rat)N/A
  • LD50 (mouse)N/A