Metabolism of 14C-labelled alphaxalone in man

The metabolism of 14C-labelled alphaxalone, dispensed as Althesin, was studied in normal patients, patients with obstructive jaundice and patients with chronic renal disease and anuria. The radioactive label was removed rapidly from the plasma following i.v. administration. The major portion of the label was excreted in the urine. In patients with normal renal function 14C-labelled alphaxalone is probably taken up by the liver, metabolized to a more polar compound and excreted in the urine; a small amount is excreted in the bile. In the patient with anuria, hepatic uptake appears to be relatively normal and the length of action of Althesin is not prolonged. It is assumed that in such patients the eventual route of excretion is via the bile and faeces.