[Plasma levels and renal excretion of [3H]-codeine phosphate in humans receiving tablets or depot capsules (author's transl)].
In two studies (a) a single 50 mg [3H]-codeine phosphate depot capsule (a special sustained-release form) and (b) two dosages of 25 mg [3H]-codeine phosphate tablets with a time lag of 4 h for the second administration were given to the same 4 healthy volunteers. In both studies plasma level and renal excretion of the radioactivity and plasma level of the specifically extracted unchanged drug were measured. The renal exretion was nearly complete within 48 h in both studies. The relative bioavailability of the [3H]-codeine phosphate released from the capsule and from the two tablets was shown to be the same comparing the areas under the plasma level curves. Assuming that the effective codeine plasma level is about 20 ng/ml a cough preventing period of at least 8 h after administration of a codeine depot capsule can be concluded from the given results.
D000328:Adult; D002214:Capsules; D003061:Codeine / Q000008:administration & dosage* / Q000378:metabolism; D003692:Delayed-Action Preparations; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D013607:Tablets
D002214:Capsules; D003692:Delayed-Action Preparations; D013607:Tablets; D003061:Codeine
Plasmaspiegel und renale Ausscheidung von [3H]-Codeinphosphat beim Menschen nach Gabe von Tabletten und Depotkapseln.