Upprepad intravenös administrering av trimetoprim-sulfadiazin hos neonatala föl
Eight healthy 3-day-old foals were given repeated injections of trimethoprim-sulfadiazine intravenously for 3 days, at a dosage of 15 mg/kg bodyweight (2,5 mg trimethoprim and 12,5 mg sulfadiazine). Blood samples were collected prior to each administration and for the following 24 hours after last administration. Serum concentrations of trimethoprim and sulfadiazine were measured and the pharmacokinetics for the substances were studied. The elimination half time (t½) and clearance (ClB) for trimethoprim and sulfadiazine for the foals did not diverge from adult horses. According to these data it is possible to assume that the same dose interval and dose can be used for foals as for adult horses. However, in this study the plasma concentrations do not exceed MIC (minimum inhibitory concentration) for the most common sepsis pathogens during the entire dose interval. Therefore, it may be recommended to administer trimethoprim-sulfadiazine at a dosage of 15 mg/kg bodyweight three times daily in foals.