Excretion and biotransformation of alfentanil and sufentanil in rats and dogs.

摘要: The excretion and biotransformation of alfentanil (ALF) sufentanil (SUF), two recent analogues the synthetic opioid fentanyl, were studied after single iv administration tritium-labeled drugs in male rats dogs. almost completely metabolized species, which resulted a large number metabolites. metabolites was rapid exceeded 95% within 4 days, except for that ALF dogs (about 85%). For ALF, radioactivity with urine (73% rats, about 76% dogs) feces. SUF, amounted to 38 60% feces 62 40%, dogs, respectively. Bile-cannulated excreted 68% bile 24 hr SUF dosing, 22% this biliary subjected enterohepatic circulation. After an dose, 24%, circulation minimal. main metabolic pathways oxidative N-dealkylation at piperidine nitrogen amide nitrogen, O-demethylation, aromatic hydroxylation, formation ether glucuronides. N-[4-(Hydroxymethyl)-4-piperidinyl]-N-phenylpropanamide (M6) metabolite both rats. In glucuronide N-(4-hydroxyphenyl)propanamide (M5) ALF. dosing N-[4-(methoxymethyl)-4-piperidinyl]-N-phenylpropanamide more abundant than M5.