Bioavailability and tissue elimination of chloramphenicol following parenteral administration in the preruminant calf.

The serum bioavailability of a preparation based on chloramphenicol in dimethylsulfoxide and glycerol formal was determined after intravenous (IV) and intramuscular (IM) injection, and a treatment schedule combining both routes of administration in calves. The dosage-level applied was 30 mg/kg. Pharmacokinetic parameters after administration were determined and a residue study was performed for chloramphenicol in the tissues after the treatment such as it is normally prescribed. Serum concentrations obtained were such that the potential therapeutic level of 5 micrograms/ml was maintained for more than 12 hours after IV administration and for more than 20 hours after IM application. The biological half-life was 6 hours and the volume of distribution was approximately 1.2 l/kg. No adverse reactions were observed, thus, demonstrating the perfect tolerance of the preparation. The tissue residue evaluation shows that, first, the compound does not accumulate in any organ in particular and, secondly, that it is rapidly eliminated after the treatment.