Chloramphenicol sodium succinate in the horse: serum, synovial, peritoneal, and urine concentrations after single-dose intravenous administration.

The research investigates the concentration of chloramphenicol sodium succinate, a medicine given to horses, in different body fluids after a single intravenous dose. The study reveals that the highest concentration was found half an hour after administration, and the drug was no longer detectable in the serum, synovial or peritoneal fluids after 3 to 6 hours.

Study Design and Subjects

• The study involved six healthy adult mares, which were given a single intravenous (IV) dose of chloramphenicol sodium succinate. The dosage used was 25 mg/kg of the horse’s body weight.

Measurement of Chloramphenicol Concentrations

• After administering the drug, the researchers measured the concentrations of chloramphenicol in the serum, synovial fluid (fluid found in the cavities of joints), peritoneal fluid (liquid in the abdominal cavity), and urine of the mares over a 48-hour period.

Findings and Observations

• The highest concentration of chloramphenicol in the serum was recorded as 6.21 micrograms/ml, half an hour after drug administration.
• The drug was also identified in synovial and peritoneal fluids, which averaged peak concentrations of 3.89 micrograms/ml and 3.50 micrograms/ml respectively, also at the half-hour mark.
• The serum and synovial concentrations of the drug dropped quickly and were undetectable by the end of the third hour following administration.
• In peritoneal fluid, the medicine was not detectable after six hours.
• The serum half-life of chloramphenicol was established as 0.43 hour which indicates that it takes approximately half an hour for half of the drug to be eliminated from the serum.
• The apparent volume of distribution (the theoretical volume that would be necessary to contain the total amount of an administered drug at the same concentration that it is observed in the blood plasma) was calculated as 2.83 L/kg.
• Chloramphenicol peaked in the urine half an hour after administration as well, with a concentration level of 106.72 micrograms/ml, after which it also diminished rapidly. The drug was no longer detectable in the urine 36 hours after administration.

Implications

• The findings from this research could be useful for veterinary clinicians when deciding on treatment strategies. The duration of drug detectability could help in determining future dosage intervals.
• The study gives a clear picture of how fast the body metabolizes and eliminates the chloramphenicol sodium succinate drug.