Antimicrobial selection, administration and dosage

Various types of information contribute to the selection of an antimicrobia l agent. Initial requirements are diagnosis of the site and nature of the i nfection, assessment of the severity of the infectious process and medical condition of the diseased animal; these are embodied in clinical experience . Additional considerations include identification of the causative pathoge nic microorganism, knowledge of its susceptibility to antimicrobial agents (microbiological considerations) and of the pharmacokinetic properties of t he drug of choice and alternative drugs, and their potential toxicity (phar macological considerations) in the animal species. Select an antimicrobial drug and dosage form appropriate for use in the particular animal species. Usual dosage regimens may be applied, except in the presence of renal or he patic impairment, when either modified dosage or a drug belonging to anothe r class should be used. The duration of therapy is determined by monitoring the response both by clinical assessment and bacterial culture. A favourab le clinical response is the ultimate criterion of successful therapy.