Objective:To identify how ‘elderly’ patients are defined and considered within Australian clinical guidelines for the use of pharmacotherapy.Method:Guidelines pertaining to the use of pharmacotherapy, focusing on conditions described in National Health Priority Areas, were identified using databases (Medline, Google Scholar) and organisation websites (Department of Health and Ageing, National Heart Foundation, National Health and Medical Research Council). Guidelines were reviewed and qualitatively analysed to identify any references or definitions of ‘elderly’ persons.Results:Among the 20 guidelines reviewed, 3 defined ‘elderly’ by chronological age (i.e., years since birth) while the remaining 17 guidelines did not define ‘elderly’ in any way. All 20 guidelines used the term ‘elderly’, whilst some guidelines provided age (chronological)-based dosage recommendations suggesting an ageist or generalist approach in their representation of ‘elderly’, for which rationale was seldom provided. Thematic analysis of the statements revealed five key themes regarding how ‘elderly’ was considered within the guidelines, broadly describing ‘elderly’ persons as being frail and with altered pharmacology. Some guidelines also highlighted the limited evidence base to direct clinical decision-making. A continuum of perceptions of ageing also emerged out of the identified themes.Conclusion:Clinical practice guidelines currently do not adequately define ‘elderly’ persons and provide limited guidance on how to apply treatment recommendations to older persons. The representation of ‘elderly’ in guidelines needs to be less based on chronological age or generic definitions focusing more on establishing a direct link between an individual patient’s characteristics and the pharmacology of their prescribed medication. Clinical guidelines that do not offer any practical descriptions of the features of ageing that are specifically related to the use of pharmacotherapy, or how to assess these in individual patients, render decision-making challenging.