Pharmacokinetics and biotransformation of the prostacyclin analogue, ZK 36 374, in the beagle dog.

Tritium-labelled ZK 36 374 was administered to three female beagle dogs intravenously and orally in a dose of 200 micrograms/kg. Blood and plasma levels and excretion with urine and feces of drug and metabolites were measured. ZK 36 374 was rapidly absorbed. The bioavailability was estimated as about 10% of the dose. The concentration of radio-labelled compounds in the plasma declined in three phases with half-lives of 3 min, 46 min and approx. 2 d. The half-life of the unchanged drug was 14 min. ZK 36 374 was totally metabolized and excreted mainly via the kidneys.