Prescribing cascades: we see only what we look for, we look for only what we know.

Prescribing cascades are increasingly recognized since they were described in the mid-1990s. Cascades are more likely in older people with multimorbidity and associated polypharmacy where multiple medications can induce a variety of side effects that manifest with various non-specific symptoms that may be misidentified as new geriatric syndromes such as falls, dizziness and new-onset incontinence. Geriatricians encounter medication side effects frequently and will usually consider if an older patient presenting with new symptoms could be experiencing an adverse drug reaction or event. However, most medications prescribed to multimorbid older patients are initiated and continued by prescribers without specialist geriatric training who may not detect medication-induced morbidity. Therefore, novel approaches to the detection and management of prescribing cascades in older people are needed. Currently, the knowledge base surrounding prescribing cascades in older people is evolving towards better methods for cascade detection and secondary prevention. However, the large number of cascades described in the literature, the wide-ranging symptomatology of cascades and the rapidly increasing number of multimorbid older people at risk of cascades represent major challenges for prescribers. Furthermore, prospective prevalence studies of prescribing cascades in older people are lacking. To detect and correct prescribing cascades during routine medication review in multimorbid older people, awareness of cascades is essential. Prescribing cascade awareness in turn requires novel explicit ways of defining cascades to facilitate their rapid detection and correction during medication review. Given that prescribing cascades represent another aspect of inappropriate prescribing (IP), explicit cascades criteria should be integrated with other explicit IP criteria.