Therapeutic antimicrobial use should be confined to appropriate clinical indications. An accurate diagnosis includes characterization of etiology. Practitioners should strive to rule out parasitism, mycotoxicoses, nutritional imbalances, and viral infections. Secondary bacterial pathogens may require antimicrobial therapy. Therapeutic exposure to antimicrobials should be minimized by treating only for as long as needed for the desired clinical response.
Therapeutic exposure involves both dose and duration.
Continued use of antimicrobials in chronic, non-responsive clinical cases should be discouraged. Withdrawal times must always be considered during the selection of antimicrobials. Limit therapeutic antimicrobial treatment to ill or at risk animals, treating the fewest animals indicated. Consider group morbidity and mortality rates when deciding whether or not to initiate herd, group, or individual therapy. Consider the herd health history for the therapeutic use of antimicrobials in the control and prevention of disease.