PT - JOURNAL ARTICLE AU - T Walle AU - E C Conradi AU - U K Walle AU - T E Gaffney TI - O-methylated catechol-like metabolites of propranolol in man. DP - 1978 Jul 01 TA - Drug Metabolism and Disposition PG - 481--487 VI - 6 IP - 4 4099 - http://dmd.aspetjournals.org/content/6/4/481.short 4100 - http://dmd.aspetjournals.org/content/6/4/481.full SO - Drug Metab Dispos1978 Jul 01; 6 AB - Two isomeric methoxyhydroxy metabolites of propranolol have been identified in man during chronic antihypertensive propranolol therapy. The identification was based on the mass-spectral fragmentation pattern of their trifluoroacetylated derivatives. Both isomers were detected in urine as well as in plasma, mainly as glucuronic acid and/or sulfate conjugates. The amounts of these metabolites excreted in urine were linearly related (r = 0.84) to the oral propranolol dose, 10--320 mg per day. Plasma concentrations at the 320-mg daily dose ranged from 20 to 112 ng/ml. Similar isomeric methoxyhydroxy metabolites of propranolol containing a glycol or a lactic acid side-chain were also identified.