Isometamidium residues in goat tissues after parenteral administration.

Concentrations of isometamidium in goat tissues were examined at intervals following a single intravenous or intramuscular dose (0.5 mg/kg) of drug. Appreciable concentrations of isometamidium were still detectable in liver (6.78 microgram/g) and kidney (3.26 microgram/g) 12 weeks after intravenous administration. Intramuscular injections resulted in lower and less sustained tissue concentrations of the drug. Isometamidium was not detectable in adipose tissue, spleen or skeletal muscle (except at the site of injection) probably because of the limited sensitivity of the assay method, estimated at 2.3 microgram/g of tissue.