Plasma chloramphenicol concentrations in cats following intramuscular administration of three different chloramphenicol preparations

Five adult cats were given 30 mg chloramphenicol/kg by intramuscular injection on three separate occasions, using a different preparation on each occasion. The preparations were an aqueous suspension of chloramphenicol, a solution of chloramphenicol in methylpyrrolidone, and an aqueous solution of chloramphenicol sodium succinate. Plasma chloramphenicol concentrations were determined chemically at fixed intervals after dosing. Chloramphenicol sodium succinate solution gave higher and more rapidly attained plasma chloramphenicol concentrations than the other two preparations. The extent of chloramphenicol absorption up to 8 h after administration was greater with the succincate ester than with chloramphenicol dissolved in methylpyrrolidone. There was no difference in bioavailability between the aqueous suspension and the solution in methylpyrrolidone.