PRINCIPLES OF ANTIBIOTIC PRESCRIBING IN THE ELDERLY

Clinicians providing care to elderly patients must appreciate the subt le clinical manifestations that herald the onset of life-threatening i nfectious disease. Aged patients with an infection may have neither fe ver nor leucocytosis, making diagnosis challenging. Often, the early f eatures of infectious disease are nonspecific and may resemble inflamm atory or neoplastic processes, or there may be insufficient time to aw ait definitive laboratory confirmation, and empirical antimicrobial tr eatment must be initiated. Aging involves inevitable deleterious alter ations in biological processes and, in many elderly patients, this is most strongly characterised by diminished renal functional capacity. T his has a major influence on antimicrobial prescribing in the elderly, because therapeutic efficacy must be achieved while minimising the ri sk of drug-related toxicity. Before prescribing an antibiotic to an ag ed patient with an infection, the clinician must be cognisant of the p atient's drug allergy history and the other drugs that the patient is taking. Ignorance of potential drug-drug interactions can result in in effective treatment or enhanced toxicity. The therapy of elderly patie nts with infections is being expanded. To reduce costs and enhance the efficiency of care, systems have been developed to provide antimicrob ial care in the home and in long term care facilities. Home healthcare has burgeoned, and drugs that are well tolerated, have a broad spectr um of activity and are simple to administer (e.g. ceftriaxone and fluo roquinolones) appear to be eminently suitable for this therapeutic rol e. Physicians must also be informed of the factors responsible for the emergence of resistant bacteria that are contributing to infections i n institutional and community settings. Clinicians should strive to cu rb inappropriate antibiotic use to stem the tide of infections that ar e caused by multidrug-resistant bacteria.